Answer:
63 km
Step-by-step explanation:
Given :
Speed = 315 km/hTime = 12 minutesSolving :
Convert minutes into hours so that the units are equal, otherwise your answer will not be correct.
There are 60 minutes in an hourTherefore, 12 minutes is equal to :12/60 hours1/5 hours0.2 hoursCalculating distance
Distance = Speed x TimeDistance = 315 km/h x 0.2 hDistance = 63 kmAnswer:
frist convert 315k/h into m/s
then convert 12min into sce
=12*60
=720
distance = v*t
=315*720
=226800m
find the values of x and y in the following triangle
What is 7 as a complex number?
Complex number is in the form a +bi
As given in the question, a = 7 b = 0
therefore, the answer is 7 + 0i
Complex Number :The complex number is basically the combination of a real number and an imaginary number. The complex number is in the form of a + ib, where a = real number and ib = imaginary number. Also, a , b belongs to real numbers and i = √-1.
Hence, a complex number is a simple representation of addition of two numbers, i.e., real number and an imaginary number. One part of it is An equation of the form z= a+ib, where a and b are real numbers, is defined to be a complex number. The real part is denoted by Re z = a and the imaginary part is denoted by Im z = ib.
Z = a + bi purely real and the other part is purely imaginary.
Real Number:Any number which is present in a number system such as positive, negative, zero, integer, rational, irrational, fractions, etc. are real numbers. It is represented as Re(). For example: 12, -45, 0, 1/7, 2.8, √5, etc., are all real numbers.
Imaginary Numbers:The numbers which are not real are imaginary numbers. When we square an imaginary number, it gives a negative result. It is represented as Im(). Example: √-2, √-7, √-11 are all imaginary numbers.
For Example:
The complex numbers were introduced to solve the equation x2+1 = 0. The roots of the equation are of form x = ±√-1 and no real roots exist. Thus, with the introduction of complex numbers, we have Imaginary roots.
We denote √-1 with the symbol ‘i’, which denotes Iota (Imaginary number).
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Solve for x in the following 4/2.6=5/x
The value of X is 3.25
Look at the attached picture
Hope it will help you
Good luck on your assignment
The graph shown matches which quadratic equation?
A)
y=x²+2
B)
y = x2 - 2
y = (x - 2)2
(
x27²
40)
The exponential function y = 2(3) grows by a factor of 9 between x = 1 and x = 3. What factor does it gro
= 72
Answer:
A unless that's division its not
Step-by-step explanation:
every other factor goes to -2 this one doesn't and it matches the graph
(sorry if i got the answer wrong i kinda dont remember much but its fine)
Explain how the interquartile range of a data set can be used to identify outliers. The interquartile range (IQR) of a data set can be used to identify outliers because data values that are ▼ less than equal to greater than ▼ IQR Upper Q 3 minus 1.5 (IQR )Upper Q 3 plus IQR Upper Q 3 plus 1.5 (IQR )or ▼ less than equal to greater than ▼ IQR Upper Q 1 plus 1.5 (IQR )Upper Q 1 minus IQR Upper Q 1 minus 1.5 (IQR )are considered outliers.
Answer:
- greater than Upper Q 3 plus 1.5 (IQR)
- less than Upper Q 1 minus 1.5 (IQR)
Step-by-step explanation:
To identify outliers the interquartile range of the dataset can be used
Outliers can be identified as data values that are
- greater than Upper Q 3 plus 1.5 (IQR)
- less than Upper Q 1 minus 1.5 (IQR)
Using the interquartile range concept, it is found that:
The interquartile range (IQR) of a data set can be used to identify outliers because data values that are 1.5IQR less than Q1 and 1.5IQR more than Q3 and considered outliers.
----------------------------
The interquartile range of a data-set is composed by values between the 25th percentile(Q1) and the 75th percentile(Q3).It's length is: \(IQR = Q3 - Q1\)Values that are more than 1.5IQR from the quartiles are considered outliers, that is:\(v < Q1 - 1.5IQR\) or \(v > Q3 + 1.5IQR\)
Thus:
The interquartile range (IQR) of a data set can be used to identify outliers because data values that are 1.5IQR less than Q1 and 1.5IQR more than Q3 and considered outliers.
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A cruise ship can cover 19 nautical miles in 437 minutes. How many nautical miles will it travel in 345 minutes?
The cruise ship will travel approximately 15 nautical miles in 345 minutes.
How did we get the value?Use a proportion to solve this problem. Let "d" be the number of nautical miles the cruise ship will travel in 345 minutes. Then:
19 nautical miles / 437 minutes = d nautical miles / 345 minutes
To solve for "d", cross-multiply:
19 nautical miles x 345 minutes = d nautical miles x 437 minutes
Then, divide both sides by 437 minutes to isolate "d":
d nautical miles = (19 nautical miles x 345 minutes) / 437 minutes
Simplifying this expression, we get:
d nautical miles = 15 nautical miles (rounded to the nearest whole number)
Therefore, the cruise ship will travel approximately 15 nautical miles in 345 minutes.
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What is the answer and plz give me step by step explaining
Answer:
7
Step-by-step explanation:54x=60x-42, -6x=-42, divide both sides by six then you get 7
Question 2
1 pts
if two dice are rolled, what is the probability that the sum of the dots on the upward is 10
solve for inequality
|x-1/2| + 4 ≤ 5/2
The solution set of the inequality |x - 1 / 2| + 4 ≤ 5 / 2 is x ≥ 2 and x ≤ - 1.
How to determine the solution set involving absolute values
In this problem we find an inequality including an absolute value, which requires some additional treatment by taking definition of absolute value into account, in order to determine the complete solution set:
For x < 1 / 2:
- x + 1 / 2 + 4 ≤ 5 / 2
- x + 9 / 2 ≤ 5 / 2
4 / 2 ≤ x
x ≥ 2
For x ≥ 1 / 2:
x - 1 / 2 + 4 ≤ 5 / 2
x + 7 / 2 ≤ 5 / 2
x ≤ - 2 / 2
x ≤ - 1
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Jacob spent 5 hours skiing and snowboarding. He skied for 2 hours 10 minutes.
How long did he spend snowboarding?
Answer:
he spent 2hours 50minutes snowboarding
the time he spent skiing and snowboarding minus the time he skied
5hours minus 2hours 10minutes
Help!! Truth Table
Thank you!!
Answer:
Step-by-step explanation:
\(\begin{array}{c|c|c|c|c}p&q&r&p \vee q&(p \vee q)\ =>\ r\\---&---&---&---&------\\T&T&T&T&T\\T&T&F&T&F\\T&F&T&T&T\\T&F&F&T&F\\F&T&T&T&T\\F&T&F&T&F\\F&F&T&F&T\\F&F&F&F&T\\---&---&---&---&------\\\end{array}\)
The random variable X represents the number of calls per hour to a call center in the last month. The probability distribution for X is below. 1 2 4 5 6 7 P(x) 0.01 0.10 0.26 0.33 0.18 0.06 0.03 a. What is the missing value in the table? b. Find the mean. c. Find the variance and standard deviation. d. Interpret your results. B. In a quality control analysis, the random variable X represents the number of defective products per each batch of 100 products produced Defects (x) Batches 2 87 3 5 95 113 64 13 a. Use the frequency distribution above to construct a probability distribution? b. Find the mean. c. Find the variance and standard deviation.
a. The missing value in the table 0.03
b. The mean is 4.18
c. The variance is 3.23 and standard deviation is 1.80
d. The larger the standard deviation, the greater the spread of the probability distribution.
A random variable is a variable that can take on different values depending on the outcome of a random event. In this case, the random variable X represents the number of calls per hour to a call center in the last month.
a. The missing value in the table is the number of calls per hour for the probability 0.03. From the table, we see that the number of calls per hour is 7.
b. The mean, also known as the expected value, is a measure of the center of the probability distribution. It is calculated by taking the sum of the product of each possible value of X and its corresponding probability. In mathematical terms, the mean of X is given by:
E(X) = 1 * P(1) + 2 * P(2) + 4 * P(4) + 5 * P(5) + 6 * P(6) + 7 * P(7)
E(X) = 0.01 + 0.2 + 1.04 + 1.65 + 1.08 + 0.21 = 4.18
So, the mean number of calls per hour to the call center in the last month is 4.18.
c. The variance of X is a measure of the spread of the probability distribution. It is calculated by taking the sum of the squared differences between each possible value of X and the mean, multiplied by the corresponding probability. In mathematical terms, the variance of X is given by:
Var(X) = (1 - 4.18)² * P(1) + (2 - 4.18)² * P(2) + (4 - 4.18)² * P(4) + (5 - 4.18)² * P(5) + (6 - 4.18)² * P(6) + (7 - 4.18)² * P(7)
Var(X) = 3.23
The standard deviation is the square root of the variance, and it is also a measure of the spread of the probability distribution. In mathematical terms, the standard deviation of X is given by:
=> SD(X) = √(Var(X)) = √(3.23) = 1.80
d. Interpretation:
The mean of 4.18 calls per hour represents the average number of calls to the call center in the last month.
The standard deviation of 1.80 indicates that the number of calls per hour deviates from the mean by approximately 1.80 calls on average.
This means that about 68% of the time, the number of calls per hour will be between 2.38 (4.18 - 1.80) and 6.08 (4.18 + 1.80).
Complete Question:
The random variable X represents the number of calls per hour to a call center in the last month. The probability distribution for X is below.
x 1 2 4 5 6 7
P(x) 0.01 0.10 0.26 0.33 0.18 0.06 0.03
a. What is the missing value in the table?
b. Find the mean.
c. Find the variance and standard deviation.
d. Interpret your results.
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PLEASSEEEE HELP ASAP , WHAT IS THE SHAPE OF THE BASE AND SURFACE AREA?
Answer:
Total surface area : 733
The shape of the base is a rectangle with sides 11 in. and 12 in.
Step-by-step explanation:
The shape of the base is a rectangle with sides 11 in. and 12 in.
The surface area is the sum of the areas of the 5 sides.
Area of the base = 11*12 = 132
Area of the two triangles = (11*16)/2 = 88
Area of the back rectangle = 192
The theorem of Pitagora to find the oblique side: square root of (11*11 + 16*16)= 19.42 in.
So the area of the oblique face: 19.42* 12 = 233 (almost :) )
So total surface area: 132 + 88*2+192+233= 733 square in
Choose the best graph that represents the linear equation:
-x = 2y + 1
The line slants downward from left to right, indicating that as x increases, y decreases.
The given linear equation is -x = 2y + 1. To represent this equation graphically, we need to rearrange it into the slope-intercept form, which is y = mx + b, where m represents the slope and b represents the y-intercept.Rearranging the given equation, we get:2y = -x - 1
Dividing both sides by 2:y = (-1/2)x - 1/2
The slope of the line is -1/2, which means that for every unit increase in x, y decreases by 1/2 unit. The y-intercept is -1/2, indicating that the line intersects the y-axis at (0, -1/2).
Based on this information, the best graph that represents the linear equation y = (-1/2)x - 1/2 is a straight line with a negative slope of -1/2, starting at the point (0, -1/2) and extending infinitely in both directions.
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solving quadratic equation using the completing the square method. (a).x²+20x-12=0
Answer:
\(x = -10 + 4 \sqrt7 \ , \ x = -10 - 4 \sqrt7\)
Step-by-step explanation:
x²+20x-12=0
a = 1, b = 20, c = -12
\(x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2x}\)
\(x = \frac{-20 \pm \sqrt{448}}{2}\\\\x = \frac{-20 \pm \sqrt{8 \times 8 \times 7}}{2}\\\\x = \frac{-20 + 8\sqrt{7}}{2} \ , \ x = \frac{-20 - 8 \sqrt7}{2}\\\\x = \frac{-10 + 4\sqrt{7}}{1} \ , \ x = \frac{-10 - 4 \sqrt7}{1}\\\\x = -10 + 4 \sqrt7 \ , \ x = -10 - 4 \sqrt7\)
a coat at a store is originally priced at $54.99. the marks the price down to $32.99. to the nearest percent, what is the percent markdown of the coat?
Let f (x) = x - 4 . Graph g(x) = f (5x)
Choose the description of the transformation from the graph of f to the graph of g.
A.) The graph of g is a horizontal stretch of the graph of f by a factor of 5.
B) The graph of g is a horizontal shrink of the graph of f by a factor of 1/5
C) The graph of g is a vertical stretch of the graph of f by a factor of 5
D) The graph of g is a vertical shrink of the graph of f by a factor of 1/5
And what points would be plotted on a graph?
The graph of g(x) is on the image at the end, and the correct option for the transformation is B.
Which is the transformation applied?We define a horizontal dilation of scale factor k as:
g(x) = f(k*x)
if k > 1, we have a stretch.
if 0 < k < 1, we have a shink of scale factor 1/k
Here we have:
g(x) = f (5x) = 5x - 4
We can notice that k = 5, then we have a stretch, thus, the correct option is B.
The graph of function g(x) can be seen in the image at the end.,
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A box has a width of 10 cm and a length of 17 cm. The volume of the box is decreasing at a rate of 527 cubic cm per minute, with the width and length being held constant. What is the rate of change, in cm per minute, of the height when the height is 6 cm?
Round your answer to the nearest hundredth. (Do not include any units in your answer.)
Therefore, the rate of change, in cm per minute, of the height when the height is 6 cm is approximately -6 cm/min.
Given,The width of the box = 10 cm Length of the box = 17 cmThe volume of the box = 527 cubic cm/minWe need to find the rate of change, in cm per minute, of the height when the height is 6 cm.We know that the volume of the box is given as:V = l × w × h where, l, w and h are length, width, and height of the box respectively.It is given that the width and length are being held constant.
Therefore, we can write the volume of the box as
:V = constant × h Differentiating both sides with respect to time t, we get:dV/dt = constant × dh/dtNow, it is given that the volume of the box is decreasing at a rate of 527 cubic cm per minute.
Therefore, dV/dt = -527.Substituting the given values in the above equation, we get:
527 = constant × dh/dt
We need to find dh/dt when h = 6 cm.To find constant, we can use the given values of length, width and height.Substituting these values in the formula for the volume of the box, we get:
V = l × w × hV = 17 × 10 × hV = 170h
We know that the volume of the box is given as:V = constant × hSubstituting the value of V and h, we get:
527 = constant × 6 cm
constant = 87.83 cm/minSubstituting the values of constant and h in the equation, we get
-527 = 87.83 × dh/dtdh/dt = -6.0029 ≈ -6 cm/min
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What are the degrees of freedom for Student's t distribution when the sample size is 16? d.f. = Use the Student's t distribution to find tc for a 0.95 confidence level when the sample is 16. (Round your answer to three decimal places.) A button hyperlink to the SALT program that reads: Use SALT.
Answer:
degrees of freedom = 15
tc= 1.746
Step-by-step explanation:
The degrees of freedom is given by n-1 where n is the sample size .
so the degrees of freedom for a t distribution is 16-1= 15
Now we have to find tc for 95% confidence interval. For this we look at the t- table under the 1-0.95= 0.05 for alpha for 15 degrees of freedom and the value is 1.746
This area is to the right side under the t distribution with the given degrees of freedom for the given alpha.
It can also be found out by other calculators such as graphing calculator.
Using the degree of freedom formula and the Tcritical distribution, the degree of freedom and Tcritical value are 15 and 2.131 respectively
Given that :
Sample size, n = 16The degree of freedom , df = n - 1Hence, the degree of freedom, df = 16 - 1 = 15
The t critical value :
Confidence level, α/2 = 0.05Tcritical = \(t_{\frac{0.05}{2}}, 15 = 2.131 \)
Hence, the Tcritical value is 2.131.
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Can someone help find the surface area, then round the answer to the nearest whole number please?
The Surface Area of cylinders are: 100 yd² , 264 m², 226 mm²
The Surface Area of Can is 219 cm².
We know the formula for Surface Area of Cylinder
= 2πrh
1. Radius = 2 yd
Height = 8 yd
So, Surface Area of Cylinder
= 2πrh
= 2 x 3.14 x 2 x 8
= 100 yd²
2. Radius = 7 m
Height = 6 m
So, Surface Area of Cylinder
= 2πrh
= 2 x 3.14 x 6 x 7
= 264 m²
3. Radius = 3 mm
Height = 12 mm
So, Surface Area of Cylinder
= 2πrh
= 2 x 3.14 x 3 x 12
= 226 mm²
4. Radius = 3.5 cm
Height = 10 cm
So, Surface Area of Can
= 2πrh
= 2 x 3.14 x 3.5 x 10
= 219 cm²
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Thompson and Thompson is a steel bolts manufacturing company. Their current steel bolts have a mean diameter of 144 millimeters, and a variance of 49 . If a random sample of 46 steel bolts is selected, what is the probability that the sample mean would differ from the population mean by more than 2 millimeters? Round your answer to four decimal places.
Answer:
0.0524 = 5.24% probability that the sample mean would differ from the population mean by more than 2 millimeters.
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal Probability Distribution
Problems of normal distributions can be solved using the z-score formula.
In a set with mean \(\mu\) and standard deviation \(\sigma\), the z-score of a measure X is given by:
\(Z = \frac{X - \mu}{\sigma}\)
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean \(\mu\) and standard deviation \(\sigma\), the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean \(\mu\) and standard deviation \(s = \frac{\sigma}{\sqrt{n}}\).
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
Mean diameter of 144 millimeters, and a variance of 49.
This means that \(\mu = 144, \sigma = \sqrt{49} = 7\)
Sample of 46:
This means that \(n = 46, s = \frac{7}{\sqrt{46}}\)
Wat is the probability that the sample mean would differ from the population mean by more than 2 millimeters?
Above 144 + 2 = 146 or below 144 - 2 = 142. Since the normal distribution is symmetric, these probabilities are equal, which means that we find one of them and multiply by two.
Probability the sample mean is below 142:
p-value of Z when X = 142, so:
\(Z = \frac{X - \mu}{\sigma}\)
By the Central Limit Theorem
\(Z = \frac{X - \mu}{s}\)
\(Z = \frac{142 - 144}{\frac{7}{\sqrt{46}}}\)
\(Z = -1.94\)
\(Z = -1.94\) has a p-value of 0.0262
2*0.0262 = 0.0524
0.0524 = 5.24% probability that the sample mean would differ from the population mean by more than 2 millimeters.
Planes A and B are shown.
m
n
B
MA
If a new line, p, is drawn parallel to line /, which
statement is true?
O
Line p must be drawn in plane B.
O Line p must be perpendicular to line m.
O Line p must be drawn so that it can lie in the same
plane as line /
O Line p must be drawn in the same plane as line n.
The line which is on the same plane can be parallel, two lines are never parallel when they are in different planes, so option C is correct.
What is a line?An object having an endless length and no width, depth, or curvature is called a line. Since lines can exist in two, three, or higher-dimensional environments, they are one-dimensional things.
Given:
The given planes are A and B,
A new line, p, is drawn parallel to line l,
Line l in the diagram is located on plane A. Line p must be drawn on plane A in order to be parallel to line l. As a result, line p, which is located on plane B, will be perpendicular to line n and parallel to lines l and n.
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The image of the remaining question is attached below.
Kuta Beve A 2 Absolute Value Inequalities Toive ewch Invexuality and wash 3) lm-21
Let's begin by identifying key information given to us:
\(undefined\)ASAP Compare the square root of one hundred thirty and one hundred eleven eighths using <, >, or =.
square root of one hundred thirty > one hundred eleven eighths
square root of one hundred thirty = one hundred eleven eighths
one hundred eleven eighths > square root of one hundred thirty
one hundred eleven eighths < square root of one hundred thirty
The square root of one hundred thirty and one hundred eleven eighths using <, >, or =.
The square root of 130 is 11.401 and the square root of 111.8 is 10.573.
Therefore, √130 > √111.8
or 11.401 > 10.573.
Hence, the square root of one hundred thirty > one hundred eleven eighths.
What is a square root?
The opposite of squaring an integer is finding its square root. The result of multiplying a number by itself yields its square value, whereas the square root of a number may be found by looking for a number that, when squared, yields the original value. It follows that a = b if "a" is the square root of "b." Every integer has two square roots, one of a positive value and one of a negative value because the square of any number is always a positive number. For instance, the square roots of 4 are both 2 and -2.However, the square root of a number is typically only expressed as the positive value.The square root of a number gives the original number when the number is multiplied by itself.The square root is the inverse of squaring, that is √x = y or x² = y.The symbol square root is denoted by √ .To learn more about square root, visit:
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A circle has a radius of 9 inches. What is the area of the circle?
PLS ANSWER ASAP You get a lot of points
Answer:
254.47 in²
Step-by-step explanation:
Hello!
Recall that the area of a circle is represented by the formula: \(A = \pi r^2\)
The radius is r.
We have the radius, 9in, so simply plug it into the formula to solve for the area.
Solve for the area:
A = πr²A = π(9in)²A = 81in²πA = 254.4690049408 ≈ 254.47in²The area is approximately 254.47²in.
At a local drive-thru restaurant, 3 out of every 8 drinks sold are diet drinks. If the restaurant sells 4,200 drinks in one month, how many would be diet drinks?
Answer:
1575
Step-by-step explanation:
3/8 as a decimal is .375. Multiply 4200 by .375 to get your answer.
The y -intercept of the line whose equation is x - y = -1 is
0
1
-1
Answer:
1
Step-by-step explanation:
y- intercept occurs at x= 0. Thus, the y-intercept of a line can be found by substituting x= 0 into it's equation.
x -y= -1
When x= 0,
0 -y= -1
-y= -1
Divide both sides by -1:
y= -1 ÷(-1)
y= 1
Thus, the y-intercept is 1.
Which expressions are equivalent to 3 (6e + 4) + 8 (e + 2) + 6e ? Select all that apply.
A.28 + 32e
B.2e+5(6e+4)+24
C.4(8e+28)
D.23e + 28
E.4(8e+7)
Answer:
28+32e and 4 (8e+7)
Step-by-step explanation:
I did the quiz
The expressions equivalent to 3 (6e + 4) + 8 (e + 2) + 6e are : 4(8e + 7) And 28 + 32e
What are equivalent expressions?Those expressions that might look different but their simplified forms are the same expressions are called equivalent expressions. To derive equivalent expressions of some expressions, we can either make it look more complex or simple. Usually, we simplify it.
Given the expression as;
3 (6e + 4) +8 (e + 2) + 6e.
Expand the brackets ;
18e + 12 + 8e + 16 + 6e
Now Collect like terms together and simplify;
=18e + 8e + 6e + 12 + 16
=32e + 28
=28 + 32e
Then factorizing the result, we have;
32e + 28 = 4(8e + 7)
The expressions equivalent to 3 (6e + 4) + 8 (e + 2) + 6e are : 4(8e + 7) And 28 + 32e
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Please help with this math question!
Answer:
\(2000 {(1 + \frac{.07}{12}) }^{5 \times 12} = 2835.25\)
Choose a correct sentence
a) I don’t go to work tomorrow unless I feel better
b) I will buy this car if I’ll like it
c) I’ll tell when I hear from him
d) I’m not usually attending such par
Answer: D
Step-by-step explanation: It is D because the: "'m" in: "i'm" means: I am. The: 'I'm" is referring to you.
in C, the: "i'll" means: I will. After the: "tell", it doesn't make sense because it's not referring to someone. In between the: "tell" and "I", you should include: you. Overall, it should've sounded like: I'll tell you when I hear from him.
In B, the: "i'll" means I will. If you say in starting at this POS, It would sound: I will buy this car if I will like it. this does not make sense because instead of: i'll, you should replace it with: I.
In A, the: "don't" doesn't make sense because saying starting at a POS: I don't go to work tomorrow unless I feel better. You should replace the: "don't" with: won't.
Overall, D is the most acceptable answer.