大学微观经济学
9.If it costs $30 to produce the first unit of a good and $28,$27,$25,$23,$24,and $25 to produce the next six units,respectively,then the minimum of the average cost curve could occur at:
\x05A)\x051 unit.
\x05B)\x052 units.
\x05C)\x053 units.
\x05D)\x055 units.
\x05E)\x05none of the above.