In the offspring, AA accounts for: the square of A; Aa: 2 times a times a; Aa is the square of a.
A accounts for 1/3 and A accounts for 2/3, so in the future: AA accounts for1/3x1/3 =1/9; aa:2x 1/3 x2/3 = 4/9； Aa: 2/3X2/3=4/9。