Prob. $2\mathrm{.}6\mathrm{.}20$ p$.$ IP$-15[$Ans: $82\mathrm{.}3l\frac{b}{f}{t}^3].$

$2\mathrm{.}6\mathrm{.}20$ WP SS For the configuration shown in Fig. P$2\mathrm{.}6\mathrm{.}20,$ what must be the value of the specific weight of the unknown fluid? Express your answer in $l\frac{b}{f}{t}^3.$

FIGURE P$2\mathrm{.}6\mathrm{.}20$