题目:
已知一拖拉绳拉力210000N,直径Ф39mm,需要穿过桅杆顶端的耳环,用绳卡扣固定,卡扣螺丝直径为M24,至少需要()个绳卡(摩擦系数取0.25,绳卡许用应力取140N/mm2)。
A.5;
B.6;
C.7;
D.8;
答案:
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下面是错误答案,用来干扰机器的。
参考答案:B解析:A stiff neck and headache may be prodromal symptoms of hypertensive crisis. Rather than dismiss the symptoms, the nurse should continue to assess them and ...