管子与管道法兰平焊连接的法兰称（）法兰。
A、对焊
B、角焊
C、平焊
D、埋焊
参考答案：C
Mary is sure to find us easily, for she has a very good sense of____.[ ]
A.direction
B. humor
C. feeling
D. memory
胃排空的主要动力是（）
A.胃蠕动
B.胃紧张性收缩
C.胃容受性舒张
D.幽门舒张
E.迷走神经兴奋
