下列关于X线球管组件的散热方式不包括()
A.密封管套,空调散热
B.密封管套,自然散热
C.密封管套,风扇散热
D.闭路油循环风冷散热
E.管套内冷水循环散热
参考答案:A
现有6道题,其中4道甲类题,2道乙类题,张同学从中任取2道题解答.试求:
(1)所取的2道题都是甲类题的概率;
(2)所取的2道题不是同一类题的概率.
The financial crisis is attacking the USA, and it is true ___ many other countries. [ ]
A. to
B. against
C. of
D. by