周长相同的圆、正方形和正三角形的面积分别为a,b和c,则a,b,c的大小关系是()。
A. a>b>c
B. b>c>a
C. c>a>b
D. a>c>b
E. A、B、C、D都不正确
查看答案
下列能够促进胆固醇代谢的水溶性维生素是
A. 维生素B1
B. 维生素B2
C. 维生素C
D. 维生素B12
E. 叶酸
When()that the principal was very strict, he didn't dare go to the office alone.
A. tell
B. told
C. was telling
D. telling
There()an old man and two bodyguards standing on the platform.
A. to be
B. being
C. is
D. are
若P(2,-1)为圆(x-1)2+y2=25的弦AB的中点,则直线AB的方程是()。
A. x-y-3=0
B. 2x+y-3=0
C. x+y-1=0
D. 2x-y-5=0
E. A、B、C、D都不正确