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.
Answer:
A,B,C, and E
Step-by-step explanation:
If there were only sandwiches bought, there would be 15, if there were only salads bought there would be 20. There’s probably more than one possibility, but that’s the best I can do, considering how long it’s been since I’ve done this type of problem. I’m all the way to learning determinants, so I really have to think to remember these. Sorry in advance if this doesn’t help at all, I’m not the best at this, but I can still try.
Answer:
Step-by-step explanation:
<u>All the points that are 7 units from the origin are on the circle:</u>
<u>The maximum and minimum values of x obtained when y = 0:</u>
So
<u>The points are:</u>