Réponse :
bonjour
30 s = 0.5 min 1 min = 60 s donc 30 s = 0.5 min
20 h = 20 x 3 600 = 72 000 s
500 ms = 0.5 s
3 j = 3 x 24 = 72 h
30 min = env 0.021 j
1/2 s = 50 ans = 50 x 12 = 600 mois
1000 ans = 1 000 x 52 = 52 000 semaines
2 jours = 48 h = 172 800 s = 172 800 000 ms
Explications :
