如图所示的通电螺线管磁场的磁感线方向，四个图中正确的是： [ ]
A.
B.
C.
D.
答案：A
In July, 2012, the 30th Olympic Games _____ in London. [ ]
A. will be held
B. be held
C. is held
D. was held
债券持有人购买可交换债券后，可以按事先约定的条件和价格将所持债券回售给上市公司股东。( )
