On December 31, 2014, Oakbrook Inc. rendered services to Beghun Corporation at an agreed price of $102,049, accepting $40,000 down and agreeing to accept the balance in four equal installments of $20,000 receivable each December 31. An assumed interest rate of 11% is imputed.

Prepare the entries that would be recorded by Oakbrook Inc. for the sale and for the receipts and interest on the following dates. (Assume that the effective-interest method is used for amortization purposes.) (a) December 31, 2014. (c) December 31, 2016. (e) December 31, 2018. (b) December 31, 2015. (d) December 31, 2017.

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