Determine whether each of the following forces is conservative. Find the potential energy function if it exists. A.) F=(x^2+y^2, y^2+z^2, z^2+x^2) B.) F=(2xyz, 2xyz, 2xyz) C.) F=(8xy+2y^2z, 4x^2+4xyz, 26z+2xy^2) D.) Given the potential energy V(x,y,z) = 14xyz^3 + 2x^2 + y^3, what is the force associated with this potential?