Answer
(a) $150KJ$
(b) zero
(c) $150KJ$
Work Step by Step
(a) We know that
$BC=4m^3-1m^3=3m^3$
and $AC=150KPa-50KPa=100KPa$
Now $W=\frac{1}{2}(3m^3)(100KPa)$
$W=150KJ$
(b) Since the internal energy of the system is directly proportional to the temperature of the system, $\Delta U\propto \Delta T$ and the change in the temperature of the system is zero, hence the internal energy of the system is zero.
(c) We know that
$Q=\Delta U+W$
We plug in the known values to obtain:
$Q=150KJ+0KJ$
$Q=150KJ$
