Part a)
The simple random sample of size n=36 is obtained from a population with

and

The sampling distribution of the sample means has a mean that is equal to mean of the population the sample has been drawn from.
Therefore the sampling distribution has a mean of

The standard error of the means becomes the standard deviation of the sampling distribution.

Part b) We want to find

We need to convert to z-score.

Part c)
We want to find

We convert to z-score and use the normal distribution table to find the corresponding area.

Part d)
We want to find :

We convert to z-scores and again use the standard normal distribution table.

So if in 2 hours you drove 80 miles the in 1 hour you have to have driven 40 miles (80m/2h)
so you have to divide the 1200 miles by the 40mph to find out how many hours the trip will take (1200m/40mph=30h)
Step-by-step explanation:
The function is as follows :

We need to find the zeroes of the function in the simplest radical form.The zero of the above function is given by :

Here,
b = 5
a = 1
c = 5
So,

Hence, the correct option is (c).
Answer:
560
Step-by-step explanation:
560÷210+÷90138 which makes the answer
It’s the mean!
good luck!!