根据所给单词的适当形式填空。

小题1:Our Chinese teacher asked us to write a 400-word __________ （composition）about the autumn. I think it’s easy.

小题2:—What has_________(happen) to your hometown recently?

—Great changes have taken place.

小题3:We have taken some _________(measure) to look for the lost boy. We can find him in danger.

小题4:We have ________(learn) a lot of knowledge from the wonderful trip.

小题5:Not all people know that light pollution does great __________ (harmful) to human’s health.

某企业对外币业务采用交易发生日的即期汇率进行核算，按月计算汇兑损益。1月 20日销售价款为20万美元产品一批，货款尚未收到，当日的市场汇率为l美元=8.25元人民币。1月31日的市场汇率为1美元=8.28元人民币。2月28日市场汇率为1美元= 8.23元人民币，货款于3月2日收回。该外币债权2月份发生的汇兑收益为( )万元。

A．0.60

B．0.40

C．-1

D．-0.40