1)
format de l'image
F = 70/52.5 =700/525 = (2x2x5x7x5) / (3x5x7x5x) = je simplifie ce qui donne (2x2) / 3 = 4/3
par le calcul
4/3=1,333...333....
70/52.5 = 1,3333...333....
2)
S= 70x52.5 =3675 mm² = 0,003675m²
3)
coefficient 588/ 0.003675 =160 000
