4. On December 31, 2010 Penfold Company's inventory burned. Sales and purchases for the year had been $1,400,000 and $980,000, respectively. The beginning inventory was $170,000; in the past Penfold,s gross profit has averaged 40% of selling price. What is the estimated cost of inventory burned? (A) $840,000 (B) $590,000 (C) $310,000 (D) $140,000