根据《刑法》规定，逃避商品检验，将必须经商检机构检验的进口商品未报经检验而擅自销售、

同一级组织中人员之间的信息交流是（）沟通。

A.横向

B.纵向

C.平等

D.平行

Several days ago， a     (shock) news broke out. A Malaysian airplane (MH370) with 239 passengers just disappeared after its departure from the airport. Almost two hours later， the plane just vanished into air，as if it never existed before.

Rumors about its     (disappear) have spread fast around the world. Some people said that the plane was kidnapped by the space aliens，the so called UFO.   has never been proved or confirmed true. Some people claim     the aircraft exploded in the midair before landing. This might be true to some extent，but we still need more confirmative proof.

The people      care most about the passengers are the family members of the passengers. They   _  (wait) anxiously and even getting desperate after waiting     (hope) for almost four days.      tortures them most is not the sad news of their beloved ones' death，     the newsless. They could get no news from anywhere or anybody about the wreckage失事.This has been driving them into craziness day by day.

We hope these people     board will soon be found well and safe， and with their family members they could get together and reunited.

如图3-5-22所示，MN、PQ为两根间距不均的金属导轨，水平放置在竖直向下的匀强磁场中，导轨的一端接阻值为10 Ω的电阻R₁和电流表，另一端接阻值为5 Ω的电阻R₂.质量为m="0.1" kg的金属棒放在导轨ab处，以初速度v₀="8" m/s滑到导轨的a′b′处，历时t="0.08" s.导轨在ab处的间距L₁="0.5" m,在a′b′处的间距L₂="1.0" m.若金属棒滑动时始终与导轨接触良好，电流表的示数保持不变，不计棒与导轨间的摩擦以及其他电阻的影响.求：

图3-5-22

（1）金属棒在导轨a′b′处的速度；

（2）电流表的示数；

（3）匀强磁场的磁感应强度.

用如图5－8甲所示的实验装置验证机械能守恒定律。

小题1:实验小组A不慎将一条选择好的纸带的前面一部分损坏了，剩下的一部分纸带上各点间的距离如图5－9所示的数值，已知打点计时器的周期为T=0.02S,重力加速度g=10m/s²;重锤的质量为m=1kg,已知S₁=0.98cm,S₂=1.42cm,S₃="1.78cm," S₄=2.18cm,重锤从B点到C点重力势能变化量是                   J，动能变化量是         J.  (结果保留三位有效数字) 

小题2:若实验小组B在验证机械能守恒定律的实验中发现，重锤减小的重力势能总是大于重锤动能的增加，其原因主要是因为在重锤下落的过程中存在阻力作用，因此想到可以通过该实验装置测阻力的大小. 根据已知当地重力加速度公认的较准确的值为g，电源的频率为f,用这些物理量求出了重锤在下落的过程中受到的平均阻力大小F＝___________（用字母g、m、f、 S_1、 S₂、S₃、S₄表示）.

为保证凝结水泵在高度真空下工作，需用生水密封盘根。。