A baseball diamond is a square whose sides are 90 ft long. Suppose that a player running from second base to third base has a speed of 30 ft I sec at...

A baseball diamond is a square whose sides are 90 ft long. Suppose that a player running from second base to third base has a speed of 30 ft I sec at the instant when he is 20 ft from third base. At what rate is the player's distance from home plate changing at that instant?