Answer:
Pressure of .2 m^3 of bricks:
Pb = ρ g H = 1.8 ρw * 9.80 m/s^2 * .20 m = 1800 * 9.8 * .2 = 3530 Pascals
ρb = 1.8 ρw = 1.8 since the density of bricks is 1.8 that of water
Pw = 1 * 9.8 * 1000 * .2 = 1960 Pascals
W = P * A pressure * Area = Force
Pnet = 1570 Pascals - pressure due to bricks under water
F = 1570 N/m^2 * .2m^2 = 63 N force on pile of bricks
