c
વાયુઓના મિશ્રણ માટે,\(\frac{{{\mu _1} + {\mu _2}}}{{\gamma  - 1}} = \frac{{{\mu _1}}}{{{\gamma _1} - 1}} + \frac{{{\mu _2}}}{{{\gamma _2} - 1}}\,\,\,\therefore \,\,\,\,\frac{{1 + 1}}{{\gamma  - 1}} = \frac{1}{{\left( {\frac{7}{5} - 1} \right)}} + \frac{1}{{\left( {\frac{5}{3} - 1} \right)}}\)

\(\therefore \,\,\,\frac{2}{{\lambda  - 1}} = \frac{5}{2} + \frac{3}{2}\,\,\,\,\,\,\,\,\therefore \,\,\,\frac{2}{{\gamma  - 1}} = \frac{8}{2}\)

\(\therefore \,\,8\gamma  - 8 = 4\,\,\,\,\therefore \,\,\,8\gamma  = 12\,\,\,\,\therefore \,\,\,\gamma  = \frac{{12}}{8} = \frac{{24}}{{16}}\)