Suppose you estimate the relationship between quantity and advertising using a regression and you find the relationship:

(a) Q = 2.811 + 19.469A

i. Your p-value on the coeffcient of A is p<0.0001 and the 95% confidence interval is [18.876, 20.063]

what would the implied optimal level of advertising?

(b) Q = 99.92 + 0.135A

i. Your p-value on the coeffcient of A is p=0.081 and the 95% confidence interval is [-0.017, 0.286]

what would the implied optimal level of advertising?