Terminal Velocity
We can calculate the terminal velocity without having to set up the spreadsheet by recognizing that there will be no acceleration and hence no increase in speed when the air resistance equals the gravity: mg = bv2; solving the terminal speed gives: vterminal = [mg/b]1/2.
Using the numbers we used earlier,
vterminal = [2 kg * 9.8 m/s2 / .03 Nt-s2/m2]1/2 = 25.56 m/s = 57 mph.