— Have you seen my e-mail about our TESL project?  

— Yes. Luckily I checked my e-mails yesterday. Normally I ______ my e-mail box for days.[ ]

A. haven't opened  

B. didn't open   

C. hadn't opened      

D. don't open

某厂2007年1月份#1机组（300MW）C级检修20天，9月份#2机组（300MW）C级检修20天，10月份#3机组（600MW）C级检修25天，其余时间全出力运行。当年厂运行小时是（）小时。

A、8220

B、7200

C、7680

D、8760