Ivy begins trading as a farmer on 1 January 2020, making up annual accounts to 31 December. Her adjusted trading profits/(losses) in the opening years are as follows:

£

year to 31 December 2020 35,600 year to 31 December 2021 15,400 year to 31 December 2022 (12,900)

(a) Compute Ivy's trading income for the first four tax years, assuming that no averaging claims are made.

(b) Compute Ivy's revised trading income for the first four tax years, assuming that the cash basis is not used and all possible averaging claims are made.