在架空电力线(35KV~110KV)附近进行起重作业时,起重机具和被吊物件与电力线最小距离为:()
A、1.5m;
B、2.0m;
C、3.0m;
D、4.0m。
参考答案:D
—Has William finished writing his graduation paper yet?
—I don’t know exactly,but he __________all day.
A.is writing
B.has been writing
C.was writing
D.wrote
消化性溃疡发生的决定因素是()
A.胃蛋白酶
B.胆盐
C.乙醇
D.胃酸
E.非甾体类药物