Halliday, Resnick & Walker — Motion in Two and Three Dimensions: Problem 123

g dependence of projectile motion. A device shoots a small ball horizontally with speed $0.200 \text{ m/s}$ from a height of $0.800 \text{ m}$ above level ground on another planet. The ball lands at distance $d$ from the base of the device directly below the ejection point. What is $g$ on the planet if $d$ is (a) $7.30 \text{ cm}$, (b) $14.6 \text{ cm}$, and (c) $25.3 \text{ cm}$?