Code for polymerization in a batch reactor demonstration?

Hi, this is one interactive simulation from Wolfram Mathematica. I cannot access the coding of simulation because of my free version. Any of you guys can share the codes of this Wolfram Mathematica here? The Wolfram Notebook also being attached here.

Your problem has nothing to do with the Mathematica version. The Input cells in the source notebook have been closed. Select the outermost cell bracket in a group and then from the menu `Cell / Grouping / Open All Subgroups.