Shawn Bixby borrowed $36,000 on a 120-day, 12% note. After 65 days, Shawn paid $3,900 on the note. On day 95, Shawn paid an additional $5,900. Use ordinary interest.

a. Determine the total interest use the U.S. Rule. (Do not round intermediate calculations. Round your answer to the nearest cent.) Total interest $

b. Determine the ending balance due use the U.S. Rule. (Do not round intermediate calculations. Round your answer to the nearest cent.)

Ending balance due