At the beginning of the year, Lakeview Corporation has 660 life vests in inventory. The company wants to have 2,100 vests in inventory at the end of the year and plans to sell 6,400 life vests during the year. How many life vests must Lakeview Corporation produce during the year?
a. 8,500
b. 3,640
c. 7,840
d. 9,160