What is the pressure at the very bottom of a lake, which is 432 ft deep? (assume an air pressure of 1.013 ✕ 105 pa.) ?

Preasure at the bottom would be Air Pressure at the top added to the pressure due to the water height.

so pressure = air pressure + hdg

where,

h = depth of the lake, (432ft into metres)

d = density of water (1000kg/m^3)

g = 9.81 m/s^2 (approx.)