Answer:
x = 1
Step-by-step explanation:

Hope this helps.
Answer:
a) The margin of error for a 90% confidence interval when n = 14 is 18.93.
b) The margin of error for a 90% confidence interval when n=28 is 12.88.
c) The margin of error for a 90% confidence interval when n = 45 is 10.02.
Step-by-step explanation:
The t-distribution is used to solve this question:
a) n = 14
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 = 14 - 1 = 13
90% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 13 degrees of freedom(y-axis) and a confidence level of
. So we have T = 1.7709
The margin of error is:

In which s is the standard deviation of the sample and n is the size of the sample.
The margin of error for a 90% confidence interval when n = 14 is 18.93.
b) n = 28
27 df, T = 1.7033

The margin of error for a 90% confidence interval when n=28 is 12.88.
c) The margin of error for a 90% confidence interval when n = 45 is
44 df, T = 1.6802

The margin of error for a 90% confidence interval when n = 45 is 10.02.
Answer: 2
Step-by-step explanation:
You could write this by going 63+42 or add 63 and 42
hope that's what you are looking for ;-)<span />
Answer:
Only one extreme value of f(x) is possible.
Step-by-step explanation:
We are given the quadratic function of independent variable x which is f(x) = x² - 7x - 6 ......(1)
Now. the condition for extreme values of f(x) is 
Hence, differentiating both sides of equation (1) with respect to x, we get
= 0
⇒ x = 3.5.
So there is only one value of x for which f(x) has extreme value which is x = 3.5.
Therefore, only one extreme value of the given function is possible. (Answer)