在我国社会主义初级阶段，实行按劳分配为主体、多种分配方式并存的个人收入分配制度，下列

(14分)质量为m，电荷量为q的带负电粒子自静止开始，经M、N板间的电场加速后，从A点垂直于磁场边界射入宽度为d的匀强磁场中，该粒子离开磁场时的位置P偏离入射方向的距离为L，如图所示．已知M、N两板间的电压为U，粒子的重力不计．

(1)正确画出粒子由静止开始至离开匀强磁场时的轨迹图(用直尺和圆规规范作图)；

(2)求匀强磁场的磁感应强度B.

在受理电话举报时，要耐心．认真做笔录，有条件的可以（）。

The required fireman’s outfits required for ship’s are not to be used for any other purpose EXCEPT for the（）.

A.oxygen and explosion meter when it is used for detection of flare gases

B.self-contained breathing apparatus，when used as protection from gas leaking from a refrigeration unit

C.boots and gloves that are made of rubber or electrically non-conductive material，if used when repairing electrical equipment

D.lifeline，if used by personnel entering a compartment which might be deficient of oxygen

应急预案中可以不包括合作单位、政府部门、外援机构的清单。