根据句意及首字母提示完成单词。

1. Many people like playing computer g _____ .

2. It's Friday t _____ , and it's Saturday tomorrow.

3. What's your p_____  for this winter holiday?

4. Would you like to s _____  at home, Tony?

5. We often play football on the p _____. 

规模经济是指（）。

A.在一定时间内，产品单位成本随总销量的增加而降低

B.在一定时间内，产品单位成本随总产量的增加而降低

C.在一定时间内，产品总成本降低

D.在一定时间内，产品单位成本降低