能用简便方法的就用简便方法计算0.99乘3.5（0.75+0.9）乘0.42.5乘40.11.25乘0.25乘320.79乘4.8+0.79乘5.2加一题6.23-5.46乘0.4答得好就加多10分！！！

Question

能用简便方法的就用简便方法计算
0.99乘3.5
（0.75+0.9）乘0.4
2.5乘40.1
1.25乘0.25乘32
0.79乘4.8+0.79乘5.2
加一题
6.23-5.46乘0.4
答得好就加多10分！！！

Answer 1

0.99×3.5=（1-0.01）×3.5=1×3.5-0.01×3.5=3.5-0.35=3.15 (0.75+0.9)×4=0.75×4+0.9×4=3+3.6=6.6 2.5×40.1=2.5×（40+0.1）=2.5×40+25×0.1=100+2.5=102.5 1.25×2.5×32=1.25×2.5×4×8=（1.25×8）×（2.5...