The four corners of a baseball diamond are 90 ft apart from one another (home plate, first base, second base, third base). A certain batter is running from home plate to first base at a speed of 24 ft/s. a) When the batter is halfway to first base, how fast is the distance between second base and the batter changing? b) When the batter is halfway to first base, what can you say about how fast the distance between third base and the batter is changing without any additional calculations?