In 2019, Carson is claimed as a dependent on his parents' tax return. Carson's parents provided most of his support. What is Carson's tax liability for the year in each of the following alternative circumstances? Use Tax Rate Schedule, Dividends and Capital Gains Tax Rates, Estates and Trusts for reference.

a. Carson is 17 years old at year-end and earned $14,000 from his summer job and part-time job after school. This was his only source of income.