计算6i(]-W6k.U6Q4A+|'d+G)y9D
2009×20082007-2007×200820096i(]-W6k.U6Q4A+|'d+G)y9D
算式：提示7Q(G+P:W6i(]-W6k.U6Q4A+|'d+G)y9D
=+f-q9h:K3Z;}6^/F9l;f)F6i(]-W6k.U6Q4A+|'d+G)y9D