Use the concept of opportunity cost to explain the following. a. More people choose to get graduate degrees when the job market is poor. b. More people choose to do their own home repairs when the economy is slow and hourly wages are down. c. There are more parks in suburban than in urban areas. d. Convenience stores, which have higher prices than supermarkets, cater to busy people. e. Fewer students enroll in classes that meet before $10: 00 \mathrm{~A} . \mathrm{M}$

Short Answer: a. When the job market is poor, people choose graduate degrees because the opportunity cost (potential earnings from fewer job opportunities) is lower, and they improve their skills for better future prospects. b. When hourly wages are down, people do home repairs themselves because the opportunity cost of their time is reduced, and they save money on repairs compared to hiring professionals. c. There are more parks in suburban areas because the opportunity cost of land is lower compared to urban areas, making dedicating land for parks more affordable. d. Convenience stores cater to busy people despite higher prices because the opportunity cost of these individuals' time is high, and they value the time-saving benefit of purchasing items quickly. e. Enrollment in classes before 10:00 A.M. is lower because the opportunity cost of attending these classes (additional sleep or leisure activities) is high for many students.