ajutațima va rog frumos

Răspuns:
35 min=2.100 s
a)2100s+50s=2150 s
2 ore=7.200 s
b)200s+7.200s=7400 s
5 ore=18000s 240min=14400s
c)18000s-14400s-3540s=60s
2,5 ore=9000s 30,5 min=1830
d)9000s+1830s=10.830s