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a. Xco Ltd. paid $10,000 in bank interest during 202, and had a tax rate of 30%. Calculate the after-tax cost of interest. b. Yco Ltd had a loan outstanding in the amount of $50,000 throughout 205, with interest at 7%. Their tax rate was 25%. Calculate the after-tax cost of interest for 205. c. Refer to the solution for Example 1 in the outline. Calculate the after-tax cost of selling expense