A particular professor has noticed that the number of people, P, who complain about his attitude is dependent on the number of cups of coffee, n, he drinks. From eight days of tracking he compiled the following data:

Cups of coffee (n)	People (P)
1	12
2	10
2	10
3	10
4	6
4	6
5	5
5	5

(a) Using regression to find a linear equation for P(n). Round to 2 decimal places. P(n)P(n) =

(b) How many cups of coffee should he drink so that no one will complain about his attitude? Round to one decimal place.