3. Answer all parts (a) to (t) of this question. Consider a function 2 2 7r(:n,y) = 10 a:2 y2+a$y+be'\" +9, where a: E R, y E R and (a, b) are parameters. (b) [10 marks] Write down the first-order conditions for the problem of maximising 7 (x, y). Show that x = 0; y = 0 is a solution to the first-order conditions