Suppose Brian is a single parent with one child, and he is trying to determine the effect of transfer benefits and taxes on his implicit marginal tax rate (and thus his incentive to work). The following table shows the transfer benefits and income taxes at various income levels in the economy in which Brian resides. Compute the spendable income level Brian would have at each level of earned income and enter these values in the last column of the table. Earned Income from Work Transfer Benefits Income and Employment Taxes Spendable Income (Dollars) (Dollars) (Dollars) (Dollars) 0 9,789 0 9,789 6,000 8,611 281 12,000 7,179 794 18,000 5,302 1,314 24,000 2,156 2,159 30,000 1,408 2,705 If Brian's income from work increased from $18,000 to $24,000, his implicit marginal tax rate would be . If Brian's income from work increased from $24,000 to $30,000, his implicit marginal tax rate would be