Answer:
(a) $700
(b) $5.50
Explanation:
Weekly fixed costs = $6,000
Weekly Total meals = Average customers per day × No. of days
                 = 500 × 6
                 = 3,000
Fixed cost per meal = Weekly fixed costs ÷ Weekly Total meals
                 = $6,000 ÷ 3,000
                 = $2
(a) Lowest price in total = Number of customers × Variable costs for each meal
                    = 200 × $3.50
                    = $700
(b) Lowest price = Variable costs for each meal  + Fixed cost per meal
              = $3.50 + $2
              = $5.50