【翔翔】評論
100/2D=50cm(50/40)*(5........
1/2D=50cm 50/40=1.25x5X=5M/1M1.25X*5X*2.5D=15.625D1/0.4=2.5D2*2.5D=5D=5X=5M/1M50/40=1.25x2.5*5D*1.25=15.625D1/-0.4+2=-0.5=100/-200cm200/40cm=5X=5M/1M-0.5/-0.4=1.25X2.5*5X*1.25=15.625D