Tom studies _________ in this field than any other students in the class.
A:father
B:farther
C:further
D:more farther
如图,两个滑轮组由每个质量相同的滑轮组成.用它们分别将重物G1、G2提高相同高度( )
如图,BD是⊙O的直径,∠CBD=30°,则∠A的度数为( )
Children ____ ____ ____ like to have their own ideas.