Answer: 
Step-by-step explanation:
Confidence interval for population mean is given by :-
(1)
, where
= Sample mean
= Critical z-value
= Population standard deviation.
n= Sample size.
As per given , we have
n= 610

Significance level for 85% confidence : 
By z-table critical two tailed z-value : 
Put all values in (1) , we get




Hence, the 85% confidence interval for the mean consumption of meat among people over age 40. = 