题目

 British school starts around 9 a.m., which means students coming from China can get up an hour later ________, as schools in China begin before 8 a.m.. A. than normal       B. at a discount        C. than usual           D. by coincidence 答案：C汶川县新建的一所学校组织学生开展勤工俭学活动，五年级一班有29人共收集废纸43.5千克。平均每人收集废纸多少千克？