_____ the two buildings _____?[ ]
A. Are; like
B. Do; like
C. Is; like
D. Does; like
答案:A
四舍五入得到的近似数3.8万的精确位是( ),有效数字有( )个.
慢性风湿性心脏病病人易发生晕厥或猝死的病变基础是
A.二尖瓣狭窄
B.二尖瓣关闭不全
C.主动脉瓣狭窄
D.三尖瓣狭窄
E.肺动脉瓣关闭不全