Nasa is designing a mission to explore titan, the largest moon of saturn. titan has numerous hydrocarbon lakes containing a mix of liquid methane and liquid ethane in unknown proportions. as part of the mission, a small submersible vehicle will explore kraken mare, the largest of these lakes. assuming the maximum depth of kraken mare is less than 400 meters [m], how much total pressure in units of atmospheres [atm] must the submersible be designed to withstand? assume the surface pressure on titan is 147 kilopascals [kpa], the surface temperature is 94 kelvins [k], and the gravity is 1.35 meters per second squared [ m/s2]. the specific gravity of liquid methane is 0.415 and the specific gravity of liquid ethane is 0.546.