Suppose Mary, the owner-manager of Mary's Hot Dogs, earned $72,000 in revenue last year. Mary's explicit costs of operation totaled $36,000. Mary has a Bachelor of Science degree in mechanical engineering and could be earning $30,000 annually as a mechanical engineer.
A. Mary's implicit cost of using owner-supplied resources is $36,000.
B. Mary's economic profit is $36,000.
C. Mary's implicit cost of using owner-supplied resources is $30,000.
D. Mary's economic profit is $6,000.
E. Both c and d.