下列实验操作错误的是（ ）
A．
加入固体粉末
B．
读取液体体积
C．
加热液体物质
D．
倾倒液体物质
A、具体操作：先将试管横放，把盛药品的药匙或纸槽小心地送入试管底部，再使试管直立，图中操作正确，故A正确；
B、量取液体时，图中读数错误，读出的液体体积偏大，故B错误；
C、给液体加热时，①先预热再集中加热；②试管与桌面成约45°角，图中操作正确，故C正确；
D、取用液体时：①试剂瓶瓶口要紧挨试管口，防止液体流出；②标签向着手心，防止液体流出腐蚀标签；③瓶塞倒放桌面上，防止污染瓶塞，从而污染药品，图中操作正确，故D正确．
故选B．
For many 36 in the US, earning some money gives them a sense of 37 . By making their own money they can buy whatever they want . It also develops a sense of responsibility and independence . Most teens I know have a small sum of money . Their 38 give them an allowance (零用钱). For some ,an allowance is given every week ; for 39 , every month or so . Usually they can get 10 to 30 dollars a month from their parents . An allowance is typically based on the 40 of chores (家务), such as washing the dishes , cleaning up one’s room, taking out the trash , and 41 the floor . 42 to younger siblings (兄弟姐妹) is also regarded as worthy of extra cash , 43 some cases . Many teens also work to get 44 .Since most of my peers (同伴) are not 45 for a formal job , many choose part-time positions . These require relatively 46 time and basically no training . They can have these jobs like babysitting ; 47 younger students , offered by most schools 48 a small fee ; 49 bagging groceries at local supermarkets . 50 spending habits , most teens spend their money in a relatively carefree style . Often , a month’s allowance can be spent in just a few hours . I’m not saying that teens in US are 51 saving money . Indeed , in many situations , teens can be quite level-headed (头脑冷静) in 52 money towards college or other 53 plans . The way teens manage their money should not be seen as a 54 . It may just be a defining characteristic of their carefree 55 .
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