Computing the Tax. Mr. and Mrs. Sedlock file a joint return and have taxable income of $370,000 without considering the following information below. Determine the increase in their tax liability for the following independent fact situations.

a. They have a STCG of $20,000 and a LTCL of $12,000.

b. They have a LTCG of $30,000 due to the sale of a collectible and a LTCG of $9,000 due to the sale of General Motors stock.

c. Same as Part b except they also have a STCL of $4,4000.