A cube $0\mathrm{.}60$ m on a side is made of bronze having a specific weight of $86\mathrm{.}9k\frac{N}{m^3}.$

Determine the magnitude and direction of the force required to hold the cube in

equilibrium completely submerged $($a$)$ in water and $($b$)$ in mercury. The specific gravity

of mercury is $13\mathrm{.}6.$