Answer:
N/A
Step-by-step explanation:
The first equation doesn't make any sense.
the correct answer is C. Taxi A is the better deal for the first 7.5 miles.
Answer: 
Step-by-step explanation:
Given : Sample size : 
Sample mean : 
Standard deviation : 
Significance level : 
Critical value : 
Formula to find the confidence interval for population mean :-

Hence, a 90% confidence interval estimate of the population mean of all students = 
Check the picture below.
surely you know how much that is.