Answer:
1. Average variable rate
a. Food and wages = Food and wages expenses/ Total revenue = 155000/650000 = 0.2385 times
b. Delivery cost= Total delivery expenses/Number of mile driven = 22950/9000 = $2.5500/mile
c. Other cost = Total other expenses/ Number of items =260/20 = $13/item
2. Total cost = Total Fixed cost + Total Variable cost
= 265000 + [0.2385(a) + 2.55(b) + 13(c). a=Sales revenue, b=Number of miles driven, c=Number of items
3. If any new item is added to the menu then only the Variable expenses incurred will increase, fixed assets will remain constant. So, the total cost will go up the sum effect of 0.2385 times of revenue, $2.55 of per kilo meter driven for delivery and $13 of other charges for per item on menu.