$(15$ Points$)$ Consider the inviscid velocity field:

vec$(V)=(2x^3+Bx{y}^2)hat()+(2y^3+B{x}^{2}y)hat()$

a$)$ Find B such that the flow is incompressible.

b$)$ Find an expression for the acceleration of a fluid particle in this flow field.

c$)$ Determine the pressure gradient in each direction at point $(2,1).$