An ideal gas undergoes an irreversible adiabatic compression from $2\mathrm{.}5$ bar and $20C$ to $8$ bar. The work

required is $20\%$ greater than the work for a reversible one with same conditions. Calculate the entropy

changes of the gas.

$C_v=(\frac{5}{2})R,C_p=(\frac{7}{2})R$

$(33$ points$)$