急性心肌梗死后心肌坏死组织逐渐纤维化形成瘢痕需要（）
A.2～3周
B.4～5周
C.6～8周
D.9～10周
E.11～12周
参考答案：C
My sister doesn't like bread. She won't eat it ____________she is very hungry. [ ]
A. if
B. when
C. as
D. unless
电压比校核试验中使用电压表时，应使仪表的指示刻度不小于量程的（）。
A.1/4
B.1/3
C.2/3
D.1/2
