题目

方程x2-px+6=0的解集为M,方程x2+6x-q=0的解集为N,且M ∩N  ={2},那么p+q等于（  ） A.21      B.8         C.6    D.7 答案：A_______ his carelessness(粗心),he lost his job and stay at hone. A.Because　　 　　 B.As result　　 C.In　 case of　　　 D. Because of