Larkspur Company had cash receipts from customers in 2020 of $122,620. Cash payments for operating expenses were $103,760. Larkspur has determined that at January 1, accounts receivable was $13,830, and prepaid expenses were $20,790. At December 31, accounts receivable was $18,670, and prepaid expenses were $23,780. Compute (a) service revenue and (b) operating expenses.