A company sells goods on installment basis and the customers are required to pay the price of the goods purchased in three years, the first installment is paid in the year oif purchase. For the year 2011 its sales were $450,000, the cost of goods sold was $300,000. What amount of deferred gross profit the company reports on Dec.31,2011 a $100,000 b $150,000 c $450,000 d $50,000