A combination$-$drive reservoir contains $10MM$ STB of oil initially in place. The ratio of the original gas$-$cap volume to the original oil volume, i$.$e$.,m,$ is estimated as $0\mathrm{.}25.$ The initial reservoir pressure is $3000a$ at $150F.$ The reservoir produced $1$ MMSTB of oil, $1100$ MMscf of $0\mathrm{.}8$ specific gravity gas, and $50,000$ STB of water by the time the reservoir pressure dropped to $2800.$ The following PVT data are available:

$\backslash$table$[[$Parameters$,3000,2800$