战国时期的秦国商鞅变法共进行了几次:() ["A、4.0","B、3.0","C、2.0","D、1.0"]
防喷器静水压强度的试验介质为()。 ["A.钻井泥浆","B.带防锈剂的水","C.机油","D.液压油"]
长期存活的肾移植受者,最易发生的肿瘤是()。 ["肾癌","肝癌","黑色素瘤","Kaposi肉瘤","非霍奇金淋巴瘤"]
下列哪项不是八种常见恶性肿瘤?() ["肺癌","乳腺癌","大肠癌","胰腺癌","食管癌"]
巷道掘进遇顶板破碎,造成巷道超高,且高度超过500mm以上时,必须() ["A、在巷道两帮补挂网","B、在巷道两帮补帮锚杆","C、补挂网、补打帮锚杆滞后施工,滞后距离迎头不得大于30m","D、机组及转载机运行期间严禁补挂网、补打帮锚杆"]
玻璃的粘度对生产有何作用