$12\mathrm{.}7$ Oceans on Mars. Scientists have found evidence that Mars may once have had an ocean $0\mathrm{.}500$ km deep. The acceleration due to gravity on Mars is $3\mathrm{.}71$ m$>$s $2.($a$)$ What would be the gauge pressure at the bottom of such an ocean, assuming it was freshwater? $($b$)$ To what depth would you need to go in the earth$$s ocean to experience the same gauge pressure?