(a) Distinguish between the cost model and the revaluation model for the measurement of property, plant and equipment subsequent to its initial recognition.
(b) If the revaluation model is used, explain how revaluation gains and losses should be accounted for.
(c) A company which uses the revaluation model and prepares financial statements to 31 December each year acquired an item of property on 1 February 2019 at a cost of £5 million. On 31 December 2019, this property was revalued at £5. 2 million. On 31 December 2020, it was revalued at £4.7 million.

Explain how these revaluations should be accounted for. Also explain what would have happened if the valuations at 31 December 2019 and 2020 had been reversed.