PRS700电源装有3个分架，上面2个分架PSU显示正常，下面1个分架PSU亮黄灯，

-1.5的倒数是______．

Had they known what was coming next, they ________ second thoughts.[ ] 

A. may have  

B. could have

C. must have had 

D. might have had

学处

下列等式中错误的是______。

A．期初余额=本期增加发生额+期末余额-本期减少发生额

B．期末余额=本期增加发生额+期初余额-本期减少发生额

C．期初余额=本期减少发生额+期末余额-本期增加发生额

D．期初余额=本期增加发生额-期末余额-本期减少发生额

试述不得按一批托运的货物的规定？