标准贯入试验的实验指标是;()
A.贯入阻力;
B.锤击数;
C.贯入度;
D.标准贯入击数。
参考答案:D
在一定范围内,现金的持有成本与现金的持有量成正比。 ( )
---____________the boy in a black coat ___________the UK ?
---No. He is ____________ U.S student .
A.Is… from , a
B.Does… come from , an
C.Is… come from , an
D.Is… from , an