Susi is thinking of opening a grill business cafe (grilled/grilled). He estimates that it will cost Rp 500 million per year to rent a place, to buy baking utensils and buy other ingredients. But he had to lose Rp 90 million per year from his marketing job at the company. a. Determine the opportunity cost Susi!. b. what is Susi's opportunity cost to run the cafe business for a year? If Susi thinks he can sell Rp 20 million a year, should he open a cafe?