During the year to 30 November 2005, Amber bought goods for resale at a cost of $75,550. Her inventory at 1 December 2004 was valued at $15,740. She did not count her inventory at 30 November 2005, but she knows that her sales for the year to 30 November 2005 were $91,800. All sales were made at a markup of 20% resulting in a gross profit of $ 15 300. Based on the information above, what was the value of Amber's cost of sales at 30 November 2005? O a. $62,950 O b. $73,440 O c. $108,670 O d. $76,500