Final answer:
The student's budget constraint for entertainment is any combination of renting movies and downloading songs that does not exceed the $20 weekly budget.
Step-by-step explanation:
The student's budget constraint for entertainment is represented by the maximum amount of money they can spend on movies and songs within their entertainment budget.
With an allocation of $20 each week, each option provided represents a potential combination of movies and songs that could be rented or downloaded without exceeding the budget.
Examples of the budget constraint include:
- Renting 20 movies from Redbox
- Downloading 20 songs from iTunes
- Renting 10 movies from Redbox and downloading 10 songs from iTunes
- Renting 15 movies from Redbox and downloading 5 songs from iTunes
Each of these options totals up to $20 spent, which conforms to the budget limitation.