Problem

Now modify your program from Problem 1 to use the convection

$$b(x,t) = 5(-(x_2-0.5), x_1-0.5).$$ (5)

Create a movie of your solution using the commands getframe and movie.

Check your answer: Your solution should increase close to $x = (0.75, 0.5)$ every whole second (including $t = 0$). It should then drift off counter-clockwise in the domain in the direction of the convection, and be gradually flattened out by the diffusion, until a new drop is added at the next whole second.