急性支气管炎胸部X线检查可出现()。
A.肺气肿
B.多无改变,或肺纹理增强,肺门阴影增深
C.肺不张
D.两肺小片絮状阴影
E.两肺点状阴影
参考答案:B
It’s really __________ comfort to the professor that his son has been admitted to __________ Harvard University.
A.a , /
B.the ,/
C./ ,the
D.the,the
异步电动机空载时的效率是()。
A.0
B.50%
C.75%
D.100%