| 两块大小、形状完全相同的金属平板平行放置，构成以平行板电容器，与它相连接的电路如图所示，接通开关K，电源即给电容器充电（ ） A．保持K接通，减小两极板间的距离，则两极板间电场的电场强度减小 B．保持K接通，在两极板间插入一块介质，则极板上的电量增大 C．断开K，减小两极板间的距离，则两极板间的电势差减小 D．断开K，在两极板间插入一块介质，则极板上的电势差增大  |
BC
Last Tuesday, a little girl died after eating some fried chicken. Her father bought the chicken for her from a street seller in Fenzhuang Village, Fengtai,Beijing.After testing the girl, the doctor said she was poisoned (中毒) by nitrites(亚硝酸盐). Some experts suggest that we should buy foods with QS signs. They are safer. After hearing about the accident, many people feel more worried about the food safety because there have been many food safety problems in our country these years. For example, poisonous(有毒的) rice, oil, milk and so on have been found out recently. People feel quite afraid because these poisonous foods are rather bad for their health and even kill them. They want the government to do something to stop such poisonous foods and drinks appearing again so that they can have safe and healthy foodsand drinks. InformationCard
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