Answer
(a) $53.0MJ$
(b) $218\frac{m}{s}$
Work Step by Step
(a) According to law of conservation of energy
$\Delta E=\Delta U+\Delta K.E$
$\Delta E=mg(y_f-0)+\frac{1}{2}(v_f^2-(0)^2)$
We plug in the known values to obtain:
$\Delta E=(1865)(9.81)(2420)+\frac{1}{2}(1865)(96.5)^2$
$\Delta E=4.43\times 10^7+8.68\times 10^6$
$\Delta E=5.30\times 10^7J=53.0MJ$
(b) $\frac{1}{2}mv_f^2=mgy_f$
This simplifies to:
$v_f=\sqrt{2gy_f}$
We plug in the known values to obtain:
$v_f=\sqrt{2(9.8)(2420)}$
$v_f=218\frac{m}{s}$