The latest demand equation for your yoda vs. alien t-shirts is given by: q = −40x + 800 where q is the number of shirts you can sell in one week if you charge $x per shirt. the student council charges you $400 per week for use of their facilities, and the t-shirts cost you $4 each. find the weekly cost as a function of the unit price x.

Cost function=fixed cost + variable cost =400+(something)
okay let's think we can only sell q shirts per week and each shirt cost us 4 dollars so i think the Cost function =400+4q =400+4(-40x+800) =400-160x+3200 =-160x+3600
but i'm not sure of the this terminology

The question is kind of confusing. if it's asking how many variations of answers can you give. then do 4^5 for your answer.this would be something like the first question could be a and the 2nd c or first b next c etc. if you can, ask the teacher for a better confirmation of what it's asking. if i'm assuming correctly what it's asking, it's 625 different variations.