Easy geometry question pls help

The graph below shows the amount of money left in the school’s desk fund, f, after d desks have been purchased. for each new desk that is purchased, by how much does the amount of money left in the school’s desk fund decrease?

(6.03) what is the constant term in the expression 6x3y + 7x2 + 5x + 4? (input a numeric value only.) numerical answers expected! me pls! fast pls

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. what distance from city a is the point where the truck and the car will meet?