Is it Point C, D , B or A? I need help I don’t know this

Aschool puts on a play. the play costs $1,200 in expenses. the students charge $4.00 for tickets. there will be one performance of the play in an auditorium that seats 500 people. what is the domain of the function that shows the profit as a function of the number of tickets sold?  

How far could you drive on 50 gallons of gas

Using elimination, what is -4x+2y=-12 4x+8y=-24