Econ Help please

Q2: Harrison plans to spend 6 hours in total to study for his exams in Economics and Geography. The following table shows his expected mark on each exam based on the number of hours spent studying each course. For example, if he spends six hours to study Geography, he expects to get 84 marks in his Geography exam. Time Spent Studying Mark in Time Spent Studying Mark in Geography Geography Economics Economics 0 hours 0 0 hours 0 1 hour 25 1 hour 20 2 hours 45 2 hours 35 3 hours 60 3 hours 47 4 hours 70 4 hours 57 5 hours 78 5 hours 63 6 hours 84 6 hours 66 a) What are the 7 specific production combinations on Harrison's production possibilities frontier (PPF)? Explain how you determined these 7 production combinations. b) What is Harrison's opportunity cost of getting 57 marks in Economics? Explain or show how you arrived at your answer. c) What is Harrison's opportunity cost of increasing his mark in Geography from 60 to 78? d) Is Harrison's PPF concave to the origin? Prove your answer WITHOUT drawing Harrison's PPF. Hint: This is a very challenging question. What is the significance of a concave to the origin PPF? e) What are 2 specific and distinct methods for Harrison to increase his expected mark in both exams at the same time