Problem $2.$ A copper cube with a side length of $250mm$ is sliding down an incline on a $10m$ thick film of oil. The angle of inclination is $=15.$ Given that the density of copper $)=(8\mathrm{.}96\frac{g}{c}{m}^3$ and the dynamic viscosity of the oil $)=(7$mPa$*s,$ what is the terminal velocity of the copper block once the sliding motion has reached steady state?

Figure $2$: A copper cube is sliding down an incline on a film of oil. Figure not to scale.