A local bookstore with market power wants to use price discrimination to increase revenue. Which of the following are considered group discounts and would likely increase revenue? Choose all applicable answers.

Group of answer choices

People whose favorite color is blue receive a discount for telling the cashier that blue is their favorite color

Retirees receive a discount by presenting identification verifying their age

People receive a discount on books by their favorite author when they tell the cashier the name of their favorite author

Students receive a discount by presenting their student identification