Answer:
Range = [- 2.5, 0.5] = [ - 5/2, 1/2]
Step-by-step explanation:
Smallest value of cos α = - 1,
largest value of cos α = 1.
When cos 4x = - 1, y=3/2cos4x-1 = 3/2*(-1) - 1 = - 5/2 = - 2 1/2 = - 2.5
When cos 4x = 1, y=3/2cos4x-1 = 3/2*1 - 1 = 1/2 = 0.5
Range = [- 2.5, 0.5] = [ - 5/2, 1/2]
Answer: <u>Last option</u>

Step-by-step explanation:
The z-scores give us information about how many standard deviations from the mean the data are. This difference can be negative, if the data are n deviations to the left of the mean, or it can be positive if the data are n deviations to the right of the mean.
To calculate the Z scores, we calculate the difference between the value of the data and the mean and then divide this difference by the standard deviation.
so
.
Where x is the value of the data, μ is the mean and σ is the standard deviation
In this case
:
μ = 12 $/h
= 2 $/h
We need to calculate the Z-scores for
and 
Then for
:
.
Then for
:
.
Therefore the answer is:

Step-by-step explanation:

the answer to the question