闭式引流,引流瓶至少应低于胸腔
A.20cm
B.30cm
C.40cm
D.50cm
E.60cm
参考答案:E
---What’s wrong with Sally? ---She was ill. She ______in the rain yesterday.
A.caught
B.has caught
C.is caught
D.was caught
垃圾填埋场工程中采用HDPE膜防渗时,要严格检验HDPE膜的外观质量和(),并组织产品复验和见证取样检验。
A.均匀度
B.厚度
C.密度
D.韧度
E.强度