Eckholm Pet Grooming records all prepayments in income statement accounts. At April 30, the trial balance shows Supplies Expense HK$28,000, Service Revenue HK$92,000, and zero balances in related statement of financial position accounts. Prepare the adjusting entries at April 30 assuming 

(a) HK$4,000 of supplies on hand and 

(b) HK$30,000 of service revenue should be reported as unearned.