At noon, ship A is 90 km west of ship B. Ship A is sailing south at 20 km/h and ship B is sailing north at 10 km/h. How fast is the distance between the ships changing at 4:00 PM?
At noon, ship A is 90 km west of ship B. Ship A is sailing south at 20 km/h and ship B is sailing north at 10 km/h. How fast is the distance between the ships changing at 4:00 PM?