Question 311311
1)  On the original exam, t = 0.  So f(0) = 88 - 15ln(0+1) = 88
2)  After time > 0, you merely plug in for t and calculate.
f(2) = 71.5
f(4) = 63.9
f(6) = 58.8
f(12) = 49.5
3)  Use a graphing calculator for best results.