Which button should you press on the calculator before beginning to evaluate an expression

Two lines parallel to the same plane are parallel to eachother

Tom wants to order tickets online so that he and three of his friends can go to a water park the cost of the tickets is 16.00 per person there is also a 2.50 one-time service fee for ordering tickets online write an expression in term of n that represents the cost for n ordering tickets online

Determine the function’s value when x = -1 a. g(-1)=-3 b. g(-1)=0 c. g(-1)=1 d. g(-1)=27