How to find the flux of a vector field through a closed surface?

Question

higher mathematics

Hello. There is a task to find the flow in 2 ways: to calculate through all smooth pieces of the surface and according to Ostrogradsky-Gauss.
a (M) = (1-z)(x i + y j ) + k
sigma = (1-z)^2=x^2+y^2, 0<=z<=1
Expressing z, z = 1 - sqrt(x^2+y^2), the figure is on the z-axis < 0 starts from z=-1, and in the condition from 0 to 1. I can't decide and I can't build the figure. Help

Answer 1

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