Celina worked her way through law school as a typist. She now makes $200 per hour as a lawyer. As the result of a heavy workload, she hires a typist at $25 per hour, but Celina discovers she can type twice as fast as her new employee. Should Celina do her own typing? a. Yes, if she can continue to type twice as fast as her new employee. b. Yes, because it will cost less to do her own typing than to hire someone to do it. c. Yes, if she does not, she will waste the time invested developing her typing skills. d. No, even though Celina types faster than her new employee, her opportunity cost of doing any given amount of typing will exceed that of her new employee.