John consumes two goods, good x and good y and his preferences are represented by the utility function U(x, y) = x + 4y.

1. Draw (sketch) John's indifference curves for U(x, y) = 5, U(x, y) = 10, U(x, y) = 15.

2. Do John's preferences satisfy strict monotonicity? Explain briefly

3. Do the indifference curves you've drawn reflect preferences that are convex? Explain briefly