Queen's Gambit Accepted: Classical Defense

1.d4 d5 2.c4 dxc4 3.Nf3 Nf6 4.e3 e6 5.Bxc4 c5 6.Qe2 a6 7.dxc5 Bxc5 8.O-O Nc6 9.e4 b5