【单选题】随着植物的生长,生长在岩石裂隙中的植物加速了岩石破碎的过程,这种风化属于()。
【判断题】血瘀体质者一旦生病,很容易出现疼痛症状,遇寒吹风或情志不畅是会发作或加重。
【简答题】Water Basin—is a _______ reinforced structure designed to store water and provide a _______ upon which the rest of the cooling tower can be supported.
【单选题】Water hammer is a short lasting pressure peak travelling along the pipe. How can it be avoided in a cooling water system?
A.
Operate valves quickly
B.
start pump with closed valves
C.
start the system with open valves and empty pipes
D.
Operate valves gradually
【单选题】带电阻性负载的三相半波可控整流电路中,晶闸管承受的最大正向电压为_________,最大反向电压为_________。
【简答题】现金是具备现实购买力或法定清偿力的通货。我国的现金包括纸币、金属铸币和信用货币。 ( )