（）是冠心病最严重的临床症状。
A.心绞痛
B.急性心肌梗死
C.心律失常
D.心跳过慢
参考答案：B
I’m going to Shanghai next week, have you anything _______to your parents?[ ]
A. to buy
B. to be bought
C. to take
D. to be taken
把一个周长是18.84分米的圆平均分成两个半圆，每个半圆的周长是[ ]
A．15.42分米
B．9.42分米
C．12.24分米
