The Dress Smart bought 250 dresses for $3100; 50 dresses were sold at a markup of 150% of cost and 120 dresses at a markup of 75% of cost; 60 of the dresses were sold during a clearance sale for $15 each; and the remaining dresses were disposed of at 20% below cost. Assume all dresses had the same cost. a) How much was the total revenue from the same of all dresses? b) What was the amount of markup realized on the whole purchase?