Answer:
a) Received a $795 deposit from a customer who wanted her piano rebuilt in February.
Account                     Debit          Credit
Cash                          $795
Unearned Revenue                      $795
b) Rented a part of the building to a bicycle repair shop: $545 rent received for January.
Account                     Debit          Credit
Cash                          $545
Rent Revenue                               $545
c) Delivered five rebuilt pianos to customers who paid $14,425 in cash.
Account                     Debit          Credit
Cash                          $14,425
Service Revenue                          $14,425
d) Delivered two rebuilt pianos to customers for $7,600 charged on account.
Account                         Debit          Credit
Accounts Receivable   $7,600
Service Revenue                             $7,600
e) Received $6,400 from customers as payment on their accounts.
Account                         Debit          Credit
Cash                              $6,400
Accounts Receivable                       $6,400
f) Received an electric and gas utility bill for $750 for January services to be paid in February.
Account                         Debit          Credit
Utilities Expense           $750
Utilities Payable                                $750
g) Ordered $1,140 in supplies.
Account                         Debit          Credit
Supplies Expense         $1,140
Supplies Payable                              $1,140
h) Paid $3,400 on account in January.
Account                         Debit          Credit
Cash                                                 $3,400
Accounts Payable         $3,400
i) Paid $16,900 in wages to employees in January for work done this month.           
 Account                         Debit          Credit
Cash                                                    $16,900
Wage Expense                 $16,900           
 j) Received and paid cash for the supplies in (g).
 Account                         Debit          Credit
Cash                                                    $1,140               
Supplies Payable            $1,140