Answer:
a. Their AGI is $15,000, consisting of $5,000 of capital gains and $10,000 of wages.
b. Their AGI is $15,000, consisting of $10,000 of lottery winnings (unearned income) and $5,000 of wages.
c. Their AGI is $25,000, consisting of $20,000 of wages and $5,000 of lottery winnings (unearned income).
d. Their AGI is $25,000, consisting of $5,000 of wages and $20,000 of lottery winnings (unearned income).
e. Their AGI is $10,000, consisting of $10,000 of lottery winnings (unearned income).