Two flat parallel walls of a height of L and width of W were constructed with a narrow gap of 2B as shown in Figure 2. Under the influence of both pressure, p and gravity, g, an incompressible fluid of a constant density, density, p occupies this gap by having it flowing downwards. Starting with a sketch of the relevant shell, analyze the given flow system and subsequently show that the rate momentum balance can be presented as Equation 1: L[tyzly+ay - Tyzy] = Ay[Plz=0 Plz=z] + playg Equation 1 Fixed wall Fixed wall 2B Figure 2: Two flat parallel walls with length L, width W and narrow gap of 2B (14 marks)