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.
Arc PQR measures 210°
An intercepted arc measures twice the intercepted angle. Here, the intercepted angle is ∠PSR. Hence:
Arc PQR = 2 * ∠PSR
1.) Compute for ∠PSR first. Opposite angles in a quadrilateral measures 180°. Hence:
∠PQR + ∠PSR = 180°
75° + ∠PSR = 180°
∠PSR = 180° - 75°
∠PSR = 105°
2.) Proceed with computing Arc PQR:
Arc PQR = 2 * ∠PSR
= 2 * 105°
= 210°
Answer:
(7,48)
Step-by-step explanation
the books go up by ten and the days go up by 2
It needs to be multiplied by 20%, aka 0.2 in decimal form
you would move the decimal to the right four times giving you 782000