Mr Wu teaches ________ English, he is friendly. [ ]
A. we
B. our
C. us
D. ours
答案:C
已知圆柱的体积为16p cm3,则当底面半径r= cm时,圆柱的表面积最小.
男,28岁,咳嗽3月余,伴咳痰,胸片如图,最可能的诊断是()
A.肺结核并播散
B.支气管肺炎
C.慢性支气管炎
D.肺慢性纤维化
E.肺癌