题目

用简便方法计算下列各题。 (1) 62×18-12×18 (2) 20-7.81-2.19 (3) 22.9+9.46+10.54+7.1 答案:解:62×18-12×18 =(62-12)×18 =50×18 =900 解:20-7.81-2.19 =20-(7.81+2.19) =20-10 =10 解:22.9+9.46+10.54+7.1 =22.9+7.1+(9.46+10.54) =30+20 =50You should be careful of such a person           flatters you in your presence and speaks ill of you in behind. A. who B. that    C. as       D. which
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