我国战争史上开创了火药与冷兵器并用的时代是在（） A.北宋 B.唐代 C.元代

阅读理解。

     Peter is thirteen years old. He is in Grade Two this year. He likes to play football and watch football

matches. And he often reads newspapers. He does his best to know where and when there is going to be a

football match.  

     Now Peter is having lunch. He is listing to the radio,too. He is very happy because there is going to be

a nice football match on TV at four this afternoon. He wants to watch it very much. But he is going to have

English and Chinese lessons. He thinks hard and find a way.

     "Hello, Mrs Black," Peter says to his teacher on the phone, "Peter is ill in bed. He wants to ask for a day

off."  

     "Oh, I'm sorry to hear that." Says Mrs Black.

     "But who's that?"

     "It's my father, Mrs Black."

1. Peter is _______ years  old now.                                            

2. Peter often likes to _______ football and _______ football matches.         

3. There  is going to _______ a nice football match on TV at four this afternoon.

4. But he is going to _______ English and Chinese lessons.                      

在电能表潜动调整时，应注意使其和（）都符合要求。

A.轻载误差

B.满载误差

C.相位角误差

D.起动电流

如图所示，a、b是一对水平放置的平行金属板，板间存在着竖直向下的匀强电场。一个不计重力的带电粒子从两板左侧正中位置以初速度v沿平行于金属板的方向进入场区，带电粒子进入场区后将向上偏转，并恰好从a板的右边缘处飞出；若撤去电场，在两金属板间加垂直纸面向里的匀强磁场，则相同的带电粒子从同一位置以相同的速度进入场区后将向下偏转，并恰好从b板的右边缘处飞出。现上述的电场和磁场同时存在于两金属板之间，仍让相同的带电粒子从同一位置以相同的速度进入场区，则下面的判断中正确的是：

A．带电粒子将做匀速直线运动

B．带电粒子将偏向a板一方做曲线运动

C．带电粒子将偏向b板一方做曲线运动

D．无法确定带电粒子做哪种运动

工作前，还必须确认（）、（）、（）、限位装置、各部分电器联锁等装置的（）、（）可靠，并关好司机室门方可进行作业。

资产负债率指标的数额越大，企业的长期偿债能力就越强。( )