If you could post an explanation and equations used that would be very helpful, thank you.

Sandy's Steam Train transports tourists through old-growth redwood trees. SST sell tickets for $60 per passenger, has variable costs of $10 per passenger, and total fixed costs of $50,000 per month. SST currently sells 2,500 tickets per month. They are thinking of having an advertising campaign in May that would cost $8,000. They estimate that ticket sales would increase by 120 tickets. How much will income increase or decrease? income will increase by $2,000. income will increase by $6,000. income will decrease by $2,000. income will increase by $7,200