2.5×2= 0.5×10= 0.6×8= 2.1×2=2.8×10= 0.7×0.8= 0.04×20= 5.6+0.4=4.7+2.3= 4.5×2= 6.9－2.5= 7.2×0.8= 6×3.4= 0.62－0.32= 1.4×0.5= 0.75×100=0.02×0.5= 3.6×0.3= 6.3÷7= 5.6×100=0.75÷0.25= 0.12...