Machinery acquired at a cost of $80,000 and on which there is accumulated depreciation of $50,000 (including depreciation for the current year to date) is exchanged for similar machinery. For financial reporting purposes, present entries to record the disposition of the old machinery and the acquisition of new machinery under each of the following assumptions:

(a) Price of new, $115,000; trade-in allowance on old, $4,000; balance paid in cash.
(b) Price of new, $115,000; trade-in allowance on old, $34,000; balance paid in cash.