Answer
(a) $F_A$ is larger than $F_B$
(b) $F_A$ is equal to $F_B$
Work Step by Step
$P = P_0 + \rho~g~h$
$P$ is the pressure
$P_0$ is the atmospheric pressure
$\rho$ is the density of the liquid
$h$ is the depth below the surface
(a) For both tanks, the pressure $P$ at the bottom of the tank is the same because the depth under the surface is the same.
We know that $F = P~A$, where $A$ is the area. Since the area of the bottom of Tank A is larger than the area of the bottom of Tank B, $F_A$ is larger than $F_B$
(b) The average pressure from the surface to the bottom of Tank A is equal to the average pressure from the surface to the bottom of Tank B.
We know that $F = P~A$, where $A$ is the area. Since the area of the side of Tank A is equal to the area of the side of Tank B, $F_A$ is equal to $F_B$.
