A fluid has the following velocity profile in three dimensions: [begin{array}{ll}v_{r}=v_{o}left(r^{2} theta+theta^{2} z-r^{2} z ight) & v_{theta}=v_{o}left(theta^{2}

A fluid has the following velocity profile in three dimensions:

\[\begin{array}{ll}v_{r}=v_{o}\left(r^{2} \theta+\theta^{2} z-r^{2} z\right) & v_{\theta}=v_{o}\left(\theta^{2} z-\theta^{2} r+\theta^{3}\right) \\v_{z}=v_{o}\left(z r-z^{2} \theta\right)\end{array}\]

a. What are the nine stresses for this fluid?

b. Is the fluid incompressible?