Réponse:
a)
Vi →→→→ ? →→→→ Vf
×1,25 ×0,70
→→→→→→→→→→→
×0,875
t = 0,875×100-100 = -12,5%
b)
Vi →→→→ ? →→→→ Vf
×0,75 ×2,00
→→→→→→→→→→→
×1,50
t = 1,50×100-100 = +50%
c)
Vi →→→→ ? →→→→ Vf
×0,60 ×0,80
→→→→→→→→→→→
×0,48
t = 0,48×100-100 = -52%
d)
Vi →→→→ ? →→→→ Vf
×1,30 ×2,00
→→→→→→→→→→→
×2,60
t = 2,60×100-100 = +160%