A sewage sludge is to be transported a distance of $3 \mathrm{mi}$ through a $12 \mathrm{in}$. ID pipeline at a rate of $2000 \mathrm{gpm}$. The sludge is a Bingham plastic with a yield stress of $35 \mathrm{dyn} / \mathrm{cm}^{2}$, a limiting viscosity of $80 \mathrm{cP}$, and a specific gravity of 1.2. What size motor (in horsepower) would be required to drive the pump if it is $50 %$ efficient?