Answer: We are 95% confident that the mean SPF level of sunscreen used by all Cal Poly students is between 29.0813 and 40.0187.
Step-by-step explanation:
Given : Significance level : 
Sample size : n= 52 , which is a large sample (n>30), so we use z-test.
By using z-value table,
Critical value: 
Sample mean : 
Standard deviation : 
The confidence interval for population means is given by :-

i.e. 

Now, the 95% confidence interval for the ppopulation mean = . (29.0813, 40.0187)
Hence, We are 95% confident that the mean SPF level of sunscreen used by all Cal Poly students is between 29.0813 and 40.0187.
The last choice, since they have the same number in their square roots.
To me it is C. or D. but you would need a second opinion. Sorry.
If the jug holds only 3 7/2 ounces [13/2 ounces) of juice, the number of 2 1/2 oz. cups that can be filled is
13
----
2
------- = 13/5 cups, or 2 3/5 cups.
5
---
2
I suspect you have copied down your numbers incorrectly. Try again.