空心圆轴和实心圆轴的外径相同时,截面的扭转截面系数较大的是( )。
A.实心轴 B.空心轴C.一样大 D.无法确定
参考答案:A
Reporters are _______ to get all facts straight, present their stories fairly and never give opinions that are objective.
A. believed
B. supposed
C. thought
D. considered
I型超敏反应有明显的个体差异,可能与下列哪些因素有关()。
A.缺乏分泌型IgA
B.胆碱能神经兴奋性增高
C.易产生IgE
D.组胺酶减少或活性低
E.胆碱酯酶缺乏