Michael Howitt of Berkley, Michigan, had his gallbladder removed recently. His total bill for this one-time event, which was his only health-care expense for the year, was $13,890. His health insurance plan has a $500 annual deductible and a coinsurance provision of 80/20. Michael’s coinsurance share is limited to $2,000.

a) What portion of the bill will Michael pay?
b) What percentage of the bill will be covered by Michael’s insurance?