For each of the following errors, considered individually, indicate whether the error would cause the trial balance totals to be unequal. If the error would cause the trial balance totals to be unequal, indicate whether the debit or credit total is higher and by how much.
a. The payment of cash for the purchase of office equipment of $15,000 was debited to Land for $15,000 and credited to Cash for $15,000.
b. The payment of $3,000 on account was debited to Accounts Payable for $300 and credited to Cash for $3,000.
c. The receipt of cash on account of $1,200 was recorded as a debit to Cash for $2,100 and a credit to Accounts Receivable for $1,200.