We are given the following data:
Sample Size = n = 1000
Sample Mean = u = 15 hours
Population Standard Deviation = s = 2 hours
Since we know the population standard deviation, we can use z distribution to find the confidence interval about the mean. z value for 95% confidence interval is 1.96.
Formula for the confidence interval is:

Using the values in the formula, we get:

Therefore, the 95% confidence interval about the population mean is 14.88 hours to 15.12 hours. So B option is the correct answer.
Answer:
3. 6.40
Explanation:
Answer:
42
Step-by-step explanation:
We know that 10x + 6y = 7, and so
6(10x + 6y) = 6(7) = 42
Answer:
-72
Step-by-step explanation:
Substitute -4 in the equation
h(-4) = -20 + 13(-4)
h(-4) = -20 + -52
h(-4) = -72
-72 is the final answer
Answer:
cubic units
Step-by-step explanation:
Given is a function exponential as

The region bounded by the above curve, y =0 , x =13 is rotated about x axis.
the intersection point is at x=4
The limits for x are 4 and 13
The volume when rotated through x axis is found by

Here a = 4 and b =13
volume = 
=
.cubic units