1. Let's say Apple is considering launching the iPhone 15 and iPhone SE 4. The amount of willingness to pay by smartphone by consumer group surveyed by the market research team is as follows. Please provide an answer with explanation and calculations.

	iPhone 15	iPhone SE 4	#of consumers (million)
Fans	800	1,300	4
Others	600	750	6
Cost	200	300

(a) If Apple releases only one smartphone, find the model and optimal price strategy.

(b) If both models are to be launched, find an optimal pricing strategy. What kind of price discrimination is this? Will Apple benefit from launching both models?

(c) Let's say that the fans' willingness to pay rises to 1,300 for iPhone 15 and 1,800 for iPhone SE 4. Is there any difference in the optimal pricing strategy at this time? If so, find a new best-price strategy.