Question

A current of 2.5 A delivers 3.5 of charge

Answer 1

1 Ampere = 1 Coulomb of charge per second

2.5 A  =  2.5 C of charge per second

Time to deliver 3.5 C of charge = (3.5 C) / (2.5 C / sec)

Time = (3.5 / 2.5) (C / C-sec)

Time = 1.4 sec

A current of 2.5 A delivers 3.5 C of charge in 1.4 seconds.