题目

The engineers have rejected the employers' proposals to end the strike and the other workers have come out in _____.A. opposition   B. return     C. sympathy       D. readiness   答案：Cin sympathy 以示同情, come out 此处意为表明态度；in return 作为报答；opposition 反对;readiness 准备 (状态); 待机。下列式子正确的是（ ）A．a2+a3=a5B．a2•a3=a6C．a2•a3=a5D．a2+a3=2a5