超声波流量计对气质要求高,当天然气中含有三甘醇时,会附着在探头表面,影响声波的()。
A.发射
B.接收
C.发射和接收
D.频率
参考答案:C
乳腺癌患者其乳腺包块大小约5cm×5cm,病理诊断为:浸润性导管癌,查淋巴结见转移癌(8/20),肺部X线检查发现转移灶。此病变为哪一期()
A.0期
B.Ⅰ期
C.Ⅱ期
D.Ⅲ期
E.Ⅳ期
—Mary can't help you _______ the house. Why?
—Because she is busy _______ a hotel reservation. [ ]
A. to clean; making
B. cleaning; making
C. cleaning; to make
D. to clean; to make