Answer
a). Car batteries often rated in "Ampere-hours" or A.h.
Unit of A.h = $\frac{charge}{time}\times time=charge$
So, unit of A.h is same as that of charge.
$1 A.h=1 C/s\times 1 hr=1C/s\times 3600 s=3600C$
b). Rating of battery $=100A.h$
Current delivered by the battery = $5A$
Rating of battery = current delivering $\times$ time required to deliver the current
$100A.h=5A\times time$
So maximum time to deliver 5A steadily = $\frac{100A.h}{5A}=20h$
c). $I=5A$
$t=20h=72000s$
charge delivered = $I\times t=5\times 72000=360000C$
Work Step by Step
a). Car batteries often rated in "Ampere-hours" or A.h.
Unit of A.h = $\frac{charge}{time}\times time=charge$
So, unit of A.h is same as that of charge.
$1 A.h=1 C/s\times 1 hr=1C/s\times 3600 s=3600C$
b). Rating of battery $=100A.h$
Current delivered by the battery = $5A$
Rating of battery = current delivering $\times$ time required to deliver the current
$100A.h=5A\times time$
So maximum time to deliver 5A steadily = $\frac{100A.h}{5A}=20h$
c). $I=5A$
$t=20h=72000s$
charge delivered = $I\times t=5\times 72000=360000C$
