若1 mol某气态烃CxHy完全燃烧，需用3molO2，则[ ]
A．x＝2，y＝2
B．x＝2，y＝4
C．x＝3，y＝6
D．x＝3，y＝8
答案：B
He is a _____ boy. He plays soccer very _____.[ ]
A. well; good
B. fine; good
C. OK; well
D. good; well
男性膀胱、前列腺扫描应做什么准备？扫描范围及层厚是多少？
