The Futura Apartments model has two assumption cells and a forecast cell. They were already defined before you ran the simulation:
Cell C5 defines the assumption about occupancy — that units rented each month will vary between 30 and 40.
Cell C7 defines the assumption about operating costs — that they will average around $15,000 per month but may vary slightly.
Cell C9 defines the simulation forecast (the results). If you highlight cell C9, you can see it contains a formula that references cells C5 and C7.
By default, assumption cells are green and forecast cells are blue. For each trial of the simulation, the values within these cells change as the worksheet is recalculated.
To see this process close-up, reset the model and run it again in single-step mode. You can use the Crystal Ball Control Panel for these procedures.