I was doing C and I got 4966.7223$ for a, for b though I put the equation in the form of e^r-(1+r)=1/1000. There doesn't seem to be any appropriate next step besides putting it in Lambert form and using a W0 function, which isn't in the syllabus for the class, and solving it graphically, which the teacher wouldn't accept. Are there any non-graphical non lambert solutions for this?