题目

—Sally, could you go and help your father wash the car?—Why ____________? I’m busy now. Amy is lying on the grass doing nothing.A．meB．I C．himD．her 答案：A解析:略 一个带电的金属球，当它带的电量增加后(稳定)，其内部的场强将 [　　] A． 一定增强 B． 一定减弱 C． 可能增加也可能减弱 D． 不变