$7-$ In a pressuremeter test in a soft saturated clay, the measuring

cell volume $V{o}_o=535cm3,po=42\mathrm{.}4k\frac{N}{m}2,$

$pf=326\mathrm{.}5k\frac{N}{m}2,vo=46cm3,$ and $vf=180cm3.$

Assuming Poisson's ratio $(s$ to be $0\mathrm{.}5$ and using Figure

$3\mathrm{.}31,$ calculate the pressuremeter modulus $($Ep$).$