Teacher's Helper is a small company.r that has a subcontract to produce instructional materials for disabled children in public school districts. The owner rents several small rooms in an ofce building in the suburbs for $600 a month and has leased computer equipment that costs $480 a month. When the company.r produces 5 instructor modules, the total costs are $1350, 6 instructor modules have a total cost of $1900, and when 1' modules are produced the total costs are $2550. What is the marginal cost of the 6111 instructor module? a. $480 b. $550 c. $600 d. $650