Poisson Probability Simulation

Inspired by the article "What does randomness look like?" by Empirical Zeal, I designed
this GeoGebra worksheet to generate random distributions similar to the Poisson probability distribution.  Select the size of the grid and the number of dots to be selected at random on the grid, and the spreadsheet counts the number of squares which receive 0 dots, 1 dots, 2 dots, etc.  Compare the results with what would have been predicted by the Poisson distribution.  Then try it again with a different sized grid or a different number of dots.  Careful!  Large grids with a lot of dots may take a long time to process.