The short-run industry supply curve: a)
is of limited usefulness, since it is not relevant when markets are perfectly
competitive.
shows the total quantity supplied by all firms in an industry for each possible
price when the number of producers is given.
c)
is a meaningful concept only if all firms in the industry are identical.
is drawn on the assumption that the number of firms in the industry doesn't
d)
increase, but it allows for a decrease in the number of firms due to bankrupt
firms leaving the industry.