Calculate the velocity a spherical raindrop

A spherical raindrop 1.7 mm in diameter falls through a vertical distance of 4150 m. Take the cross-sectional area of a raindrop =πr2, drag coefficient =0.45, density of water to be 1000 kg/m3, and density of air to be 1.2 kg/m3.

(a) Calculate the speed a spherical raindrop would achieve falling from 4150 m in the absence of air drag.
(b) What would its speed be at the end of 4150 m when there is air drag?