Graph the indifference curves of the following utility functions at the levels indicated.

Graph the indifference curves of the following utility functions at the levels indicated. Use one diagram for each pair of curves. In all cases assume and can be any non-negative real numbers. (a) (b) (c) Xl + 3X2; = 3, ul = 6 = (Xl + 3X2)2 10; = 1, tL2 = 26