The sales revenue, food cost of sales, and guests served for a small fast- food carryout division of a restaurant for the past six months are given below. Month 123 2 4 5 6 Sales Revenue $258,200 274,800 285,600 289,400 298,300 304,600 Cost of Sales, Food $ 96,200 104,300 110,500 113,100 118,900 123,700 Guests Served 10,200 10,400 10,300 10,100 10,400 10,500 For each of the six months calculate average check and average costs of sales food. Using these averages, calculate an index number. Set the in- dex for month 1 at 100 and complete index numbers for the remaining five months. With the index numbers identified, convert sales revenue and cost of sales food from historic to current dollars.