燃气安全切断阀适用于工作温度为()℃的场所.
A.-10~70
B.0~50
C.-5~60
D.10~60
参考答案：A
下列哪种疾病外周血片上不会出现幼稚细胞（）
A.急性失血后贫血
B.急性红白血病
C.再生障碍性贫血
D.骨髓异常增生综合征
E.骨髓纤维化
开放作文。
请根据下面提示，写一篇短文。词数不少于50。
In an English speech competition, you are asked to describe the following picture and explain to the
judges how you understand it.
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