Isabella, a retired university teacher, earns income from two sources in 2021-22. First, Isabella receives a sum of $20,000 from an eight-year annuity, which she purchased for $130,000 (under the terms and conditions, the principal amount will not be returned to Isabella). Second, Isabella receives $24,000 from a publisher who sells books for which she holds copyrights as an author.

Required: Citing relevant legislation and cases, discuss the income tax consequences of both receipts to Isabella.