A truck caries a liquid with density ñ in a box-shape tank of length of L as shown in the sketch below. When the truck is not moving, the height of the liquid is $h_o$. As the truck accelerates, two pressure gauges, connected to the points A and B at the bottom corners of the tank, show pressures $P_A$ and $P_B$. The gravitational acceleration is g.
a) Find an equation for the acceleration of the truck if the tank is open at the top (and the walls are high enough that liquid doesn't spill),
b) Find an equation for the acceleration of the truck if the tank is closed, with no air within it.
Note: In the equations, only use the parameters given in the question.