The Stebiliskis had their water heater replaced by a plumber. A plumber charged $85 per hour and water heater cost $525. Write a variable expression for the amount of money the Stebiliskis owed the plumber.​

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. how many hours after the truck's departure will the two meet?