题目

There is________to eat at home; we have to buy some in the supermarket. A.anything             B.nothing        C.something          D.everything 答案：B甲、乙两人加工284个零件，甲每小时做48个，乙每小时做70个；甲先做1小时后，乙再与甲合做，乙做了多少时间后完成任务？请你先列方程解应用题，再根据所列方程，编一道行程问题的应用题．