1. First divide both sides by 4 to give e^(2-x) = 32. Then take logarithms.
2. Use the rule log(a) - log(b) = log(a/b) to simplify the left hand side, before exponentiating both sides.
3. Use the fact that if log_a(m) = n then m = a^n to solve for x. What restrictions do you know of when dealing with logarithms and exponentials?
4. Hints: e^(2a) = (e^a)^2, e^(-a) = 1/e^a.