Answer:
The 90% confidence interval for the mean combined fuel economy for Ford Explorers is between 22.95 and 23.63 mpg.
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 16 - 1 = 15
90% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 15 degrees of freedom(y-axis) and a confidence level of
. So we have T = 1.7531
The margin of error is:

In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 23.29 - 0.34 = 22.95 mpg
The upper end of the interval is the sample mean added to M. So it is 23.29 + 0.34 = 23.63 mpg
The 90% confidence interval for the mean combined fuel economy for Ford Explorers is between 22.95 and 23.63 mpg.
Answer:
(-2, 4)
Step-by-step explanation:
~When reflecting a point of the x-axis, the x value (or first number inside the parenthesis) does not change.
The reason the x-value does not change is because you are reflecting over the x-axis, making the point go up or down. That will change the y-value but the x-value only changes if you move to the left or the right. In this case, you can see that the point's x-value is -2, so that will not change. It's current y-value however is -4. When reflecting over an axis, the number that is changing (in this case the y-value) will just be flipped from positive to negative, or vise versa. In this case, -4 will be reflected to be 4, making point C reflected over the x-axis (-2, 4).
Letter B I have done this before
I think this problem is 3
Just divide the numbers and times them