题目

计算： （1） （2） 答案：解：原式=8x−3y3⋅x4y6 =8xy9； 解：原式=x2−4−(x2+2x+1) =x2−4−x2−2x−1 =−2x−5．  Each member country of WTO must _____ its laws and regulations and compete on the principle of fairness and co-operation. A. reply to                  B. correspond to   C. relate to               D. submit to