Answer:
The work input during this process is 371 kJ.
Explanation:
For a polytropic process, as this one, work can be computed from the formula
[tex]W=\frac{mR\left(T_2-T_1\right)}{1-n}=\frac{2.5kg \times 0.2968\frac{kJ}{kg\times K}\left(450K-250K\right)}{1-1.4}=-371kJ[/tex]
Notice that the answer units are kJ and it's negative because the work is done ON the system.
