To crash a schedule you should ______.

A) increase the time allowed on those tasks that have float
B) try to increase expenditures of time on only those tasks that are behind schedule
C) replace those workers that are not performing up to par with the busy workers
D) increase work efforts on those tasks that are on the critical path

读“地壳物质循环略图”，完成6—9题。

图示a、b、c、d岩石中，具有层理构造，且可能含有化石的岩石是（）

A.a

B.b

C.c

D.d