I need help with adjusting entries for prepaid insurance

The prepaid insurance account had a balance of $12,000 at the beginning of the year. The account was debited for $18,000 for premiums on policies purchased during the year. Journalize the adjusting entry required at the end of the year for each of the following situations: (a) the amount of unexpired insurance applicable to future periods is $13,600, (b) the amount of insurance expired during the year is $16,400.

This assignment is out of the Financial and Managerial Accounting book. Chapter 3 EX. 3-7 on page 134