物体重力的大小为Q,用细绳BA、CA悬挂(如下图所示),a=60°,若将BA绳剪断,则该瞬间CA绳的张力为()。
A.0.5Q
B.Q
C.1.5Q
D.2Q
参考答案:A
He's got himself into a dangerous situation he is likely to be accused of meeting someone. [ ]
A. where
B. which
C. while
D. why
多发性骨髓瘤治疗首选()。
A.α-干扰素
B.羟基脲
C.马法仑
D.马利兰
E.甲基苄肼