Mary Granola loves to consume two goods, grapefruits and avocados.
(a) On the graph below, the slope of an indifference curve through any point where she has more grapefruits than avocados is −2. This means that when she has more grapefruits than avocados, she is willing to give up ____ grapefruit(s) to get one avocado.
(b) On the same graph, the slope of an indifference curve at points where she has fewer grapefruits than avocados is −1/2. This means that when she has fewer grapefruits than avocados, she is just willing to give up _____ grapefruit(s) to get one avocado.
(c) On this graph, draw an indifference curve for Mary through bundle (10A, 10G). Draw another indifference curve through (20A, 20G).
(d) Does Mary have convex preferences?