Answer
a) Please see the first graph.
b) Please see the other three graphs, left to right (and top to bottom).
Work Step by Step
a) The first budget constraint ($BC_{1}$) curve is the curve assuming no taxes are paid. The second budget constraint ($BC_{2}$) is the curve assuming 15% tax is incurred.
b) The upper left graph (of the set of three) shows that the income effect is greater than the substitution effect. This happens when there is less consumption and more leisure. The upper right graph (of the set of three) shows the substitution effect (less leisure for more work) has a greater effect than the income effect. The lower left graph shows that the income effect and the substitution effect are the same, and the only decrease is in consumption.
