Answer:
The sampling distribution of
is:
.
Step-by-step explanation:
According to the Central limit theorem, if from an unknown population large samples of sizes n > 30, are selected and the sample proportion for each sample is computed then the sampling distribution of sample proportion follows a Normal distribution.
The mean of this sampling distribution of sample proportion is:
The standard deviation of this sampling distribution of sample proportion is:

The study was conducted using the data from 15,000 students.
Since the sample size is so large, i.e. <em>n</em> = 15000 > 30, the central limit theorem is applicable to approximate the sampling distribution of sample proportions.
So, the sampling distribution of
is:
.
B and D and C in that order
Answer:
The minimum guaranteed mileage is 
Step-by-step explanation:
From the question we are told that
The mean is 
The standard deviation is 
Generally for the probability to be 4% the minimum guaranteed mileage is evaluated as



=> 
=> 
From the z table, the critical value corresponding to 0.96 to the left of the curve is

So

=> 