Suppose you buy equity of Apple and Pfizer with the following rates of return

Year

Rate of Return of Apple

Rate of Return of Pfizer

1	20%		10%
2	-10%		-4%
3	8%		30%

If the probability of each year is 1/3, the E(R) of Apple and Pfizer, respectively, are:

a		7.2%, 11.8%
b		6%, 12%
c		5.9%, 13.1%
d		6%, 10%