scalar field

If f = 2x³ + 3y² + 4z, the value of line integral ∫c gradf ⋅ dr evaluated over contour C formed by the segments (-3, -3, 2)→(2, -3, 2)→(2, 6, 2)→(2, 6, -1) is

If A = 2xi + 3yj + 4zk and u = x² + y² + z², then div(uA) at (1, 1, 1) is _________.

for the scalar field $$u = {{{x^2}} \over 2} + {{{y^2}} \over 3},\,\,$$ the magnitude of the gradient at the point $$(1,3)$$ is