题目
脱式计算,能简算要简算。 (1) 60.8-7.18-12.82 (2) 30.99-(8.5+15.99) (3) 0.9+1.08+0.92+0.1 答案:60.8-7.18-12.82=60.8-(7.18+12.82)=60.8-20=40.8
30.99-(8.5+15.99)=30.99-15.99-8.5=15-8.5=6.5
0.9+1.08+0.92+0.1=(0.9+0.1)+(1.08+0.92)=1+2=33g碳和10g氧气充分反应,得到二氧化碳的质量是
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A.11g
B.12g
C.13g
D.24g