I want solutions for 6,7,8,9

I. (70 points) An individual consumes two goods, good 1 and 2. Denote the quantities of these goods consumed by X, and X2, respectively. Suppose that the individual's utility function which represents his/her preference is given by u (1, 2 2 ) = 2x1 + 2 2. (1) Draw indifference curves for utility levels 10, 20, and 30. (2) Is the consumer's preference relation monotonic? Is it convex? Justify your answers. (3) Find marginal utilities of two goods and derive the marginal rate of substitution between two goods. Is the MRS diminishing along an indifference curve? Write down the utility maximization problem of the consumer. (5) Solve the consumer's problem and find individual demand functions for both goods. Now assume that P1