Answer: 
Step-by-step explanation:
The confidence interval for population mean is given by :-

, where
is the sample proportion, n is the sample size ,
is the critical z-value.
Given : Significance level : 
Sample size : n= 85
Critical value : 
Sample proportion: 
Now, the 99% confidence level will be :

Hence, the 99% confidence interval estimate of the true proportion of families who own at least one DVD player is 
Answer:
Did you find the answer yet I’m kinda stuck
Step-by-step explanation:
Answer:
9180
Step-by-step explanation:

(5y-10)(2y-6)
10y-30y-20y+60
-40y+60
Hope that helps!