怎样简便就怎样计算28.4×101-28.4 3.6×201 3.5×0.7+5.5×0.7+0.7 4×0.8×12.5×2.5 17.5÷0.25

①28.4×101-28.4 =28.2×（100+1）=28.2×100+28.2×1=2820+28.2=2848.2；②3.6×201 =3.6×（200+1）=3.6×200+3.6×1=720+3.6=723.6；③3.5×0.7+5.5×0.7+0.7=（3.5+5.5+1）×0.7=10×0.7=7；④4×0.8×12.5×2.5=（0.8×12.5）×（4×2.5）=10×10=100；⑤17.5÷0.25×17+13=70×17+13=1190+13=1203；⑥0.94×2.5