Need help solving:

A net is dipped in a river. Determine the flow rate of water across the net if the velocity vector field for the river is given by v = (x - y. z+ y + 1, z' ) and the net is decribed by the equation y = 1 - x - z', y 2 0, and oriented in the positive y- direction. (Use symbolic notation and fractions where needed.) V d's = S