(a) D = TU\(_4\) = TU\(_3\) + MU\(_4\) = 42 + 12 = 54
E = TU\(_7\) = TU\(_6\) + MU\(_7\) = 75 + 0 = 75
F = MU\(_2\) = \(\frac{TU_2 - TU_1}{2 - 1}\) = \(\frac{29 - 25}{1}\) = 14
G = MU\(_5\) = \(\frac{TU_5 - TU_4}{5 - 4}\) = \(\frac{65 - 54}{1}\) = 11
H = MU\(_6\) = \(\frac{TU_2 - TU_1}{6 - 5}\) = \(\frac{75 - 65}{6 - 5}\) = 10
OR F = MU\(_2) = TU\(_2) - TU\(_1) = 29 - 15 = 14
(b) To draw the demand curve there must be information on both quantities and prices. In equilibrium MU = P, therefore the marginal utility column represents prices.
(c) According to the law, marginal utility falls when quantity consumed increases
In equilibrium MU = P. Therefore, for MU to fail, price must fall to encourage the consumer to consume more. In other words, it is as price falls that quantity demanded increases as shown in the demand curve