A partial adjusted trial balance of Skysong, Inc. at January 31, 2020, shows the following. Skysong, Inc. Adjusted Trial Balance January 31, 2020 Supplies Prepaid Insurance Salaries and Wages Payable Unearned Service Revenue Debit Credit $ 900 1,800 $ 900 750 Supplies Expense 800 Insurance Expense 300 Salaries and Wages Expense 3,200 Service Revenue 2,000 Answer the following questions, assuming the year begins January 1. (a) If the amount in Supplies Expense is the January 31 adjusting entry and $1,200 of supplies was purchased in January, what was the balance in Supplies on January 17 Supplies balance (b) If the amount in Insurance Expense is the January 31 adjusting entry and the original insurance premium was for one year, what was the total premium and when was the policy purchased? Total premium Purchase date (c) If $3,700 of salaries was paid in January, what was the balance in Salaries and Wages Payable at December 31, 2019? Salaries and wages payable $