Suppose it has been determined that the sales at Ewing Gallery decline after the end of an advertising campaign, with daily sales given by S\:=\:2100\left(2^{-0.2x}\right)S = 2100 ( 2 − 0.2 x ) , where S is in dollars and x is the number of days after the campaign ends. What are the daily sales 5 days after the end of the campaign?