______, so he stopped the car at once.

A．Seeing a boy lying on the road

B．On seeing a boy sitting on the road

C．The driver had seen a boy standing on the road

D．The minute the driver saw a boy seated on the road

某车间有20名工人，每人每天加工甲种零件5个或乙种零件4个．若派x人加工甲种零件，其余的工人加工乙种零件；已知每加工一个甲种零件可获利16元，每加工一个乙种零件可获利24元．

①用含x的代数式来表示该车间每天所获利润．

②若派7人加工乙种零件，那么你认为这样安排能完成每天获利1800元的利润计划吗？说明你的看法．