The first exercise is to find the various partials of CE(S, t) in order to obtain a better sense of how changes in variable affect its value. (a) Find CE(S,t) r . What does this partial mean should r increase? Should r decrease? (b) Find CE(S,t) . What does this partial mean should the value of increase? (The market is more volatile.) Should decrease? (The market calms down.) (c) Find CE(S,t) t