Please explain each step with complete explanations and step by step, and if you can't, don't give any answer!

If there is 1 consumer in the economy where he is living two periods with one good. X11 = The good consumer 1 has in period 1. x12 = The good consumer 1 has in period 2. Their utility functions look like: U 1 = ln x11 + ln x12 , U2 = x21*x22

a) Setup for competitive equilibrium b) Find the values of equilibrium allocation and price vector.