题目

补全对话 W:Hello,Han Lin. H:Hello,Xiao Hua. W: 1.  H:I’m reading about today’s newspaper.It says every week students in primary schools have a day without homework. 2.  W: I think it’s great. 3.  H: That’s impossible.But after the big exam,we’ll also have a long summer vacation and needn’t do any homework. W: I’m looking forward to it.Have you made any plans for it? H: 4. I’m going travelling.But I haven’t decided where to go.  W: 5.  H: Good idea.I also hear Taiwan is a nice place.I’ll think about it.Thank you for your advice. W: It’s a pleasure. A.Why not 小芳用200N的水平推力在水平地面上推动重为300N的箱子，10s内箱子匀速前进0.5m，在这个过程中，小芳对箱子做功的平均功率是    W，箱子与水平地面的滑动摩擦力是    N．