What was the cost of goods sold by MHR in 2011 and 2010? What was the cost

Question:

What was the cost of goods sold by MHR in 2011 and 2010? What was the cost of inventory recognized as an expense in each year? Why do the amounts differ? Calculate MHR's gross margin and gross margin percentage for 2011 and 2010. Interpret the changed in the gross margin percentage.