Q1 (2 points) Given extensional flow u = ÉxX, Uy = ÉyY₁ U₂ = ₂z, where x, y, and & are constant extensional rate along x, y and z axis, (a)

please determine the relationship between Ex, y, and ₂ if flow is incompressible; (b) with = 1.0 s1, please calculate the time for a fluid element to extend 10 times of its original dimension along z axis.