如图所示对磁感强度B、电流I和安培力F方向的相互关系,表示正确的是[ ]
A、
B、
C、
D、
答案:C
I couldn't do my homework with all that noise _____. [ ]
A. going on
B. goes on
C. went on
D. to go on
晴天时,天然光由直射光与扩散光两部分组成,在采光设计时,多采用()作为制订标准的依据。