某物质灼烧时，焰色反应为黄色，下列判断中错误的是[ ] A．

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问题选择题

某物质灼烧时，焰色反应为黄色，下列判断中错误的是[ ]

A．该物质可能是金属钠

B．该物质一定是钠的化合物

C．该物质一定含钠元素

D．该物质中可能含钾元素

答案

答案：B

填空题

阅读下面短文,并结合课文内容补充所缺信息,每个空只能填写一个形式正确、意义相符的单词。

Li Yundi, a (1) Chinese pianist, always loved music. He was (2) in 1982 in Chongqing. When he was a

small boy, he (3) hum songs and difficult (4) of music. He began to learn the accordion at the(5) of

four, and he started to learn the piano(6) he was seven. In October 2000, Li Yundi(7) part in the 14th Chopin

International Piano Competition in Poland. He (8) first prize in his group. He was(9) the first Chinese pianist

in the 70-year(10) of the competition to win this prize.

选择题

一河宽60m，船在静水中的速度为4m/s，水流速度为3m/s，则 ( )

A．过河的最小位移是75m，所用时间是15s

B．过河的最小位移是60m，所用时间是12s

C．过河的最短时间为12s，此时的位移是60m

D．过河的最短时间为15s，此时的位移是75m