QUESTION $12$

Table $13-11$

Teacher's Helper is a small company that has a subcontract to produce instructional materials for disabled children in public school districts. The several small rooms in an office building in the suburbs for $$600$ a month and has leased computer equipment that costs $$480$ a month.

Refer to Table $13-11.$ How many instructional modules are produced when marginal cost is $$1,300?$

$$ a$.4$

b$.7$

c$.8$

d$.5$