<P> The third baseman is the defensive player whose responsibility is to defend the area nearest to third base . A third baseman ideally possesses quick reaction to batted balls and a strong arm to make the long throw to first base . The distance from 3rd to 1st is about 127 feet . In the numbering system used to record defensive plays, the third baseman is assigned the number 5 . </P> <P> Home plate, formally designated home base in the rules, is the final base that a player must touch to score . Unlike the other bases, home plate is a five - sided slab of whitened rubber that is set at ground level . The use of rubber was developed by Robert Keating, who pitched one game for the 1887 Baltimore Orioles . Previously--and more dangerously--the plate was made of stone, iron, or wood . </P> <P> The dimensions of home plate are 17 inches (43.2 cm) across the front, 8.5 inches (21.6 cm) down each side, with a triangular rear of two sides of 12 inches (30.5 cm). The rear edges are at 45 degrees to the sides, making a point at the back . The plate is white and surrounded by a black strip 3 / 4 inches (1.9 cm) in width . The plate sits entirely in "fair" territory, with the two rear edges aligned with the right and left field foul lines . The length and angle requirements for home plate mandate that it is not a regular pentagon; it is a 17 inches by 8.5 inches (43.2 x 21.6 cm) rectangle with an isosceles triangle of base 17 inches (43.2 cm) and equal sides of 12 inches (30.5 cm) attached to the back . </P> <P> Both the Major League Baseball Official Rules and the Little League rulebook say the angle between the two 12 inch sides should be 90 degrees . However, the hypotenuse of a right angled triangle with two sides of 12 inches is 288 (\ displaystyle (\ sqrt (288))) inches, which is slightly less than the 17 inches required . The home plate as specified is therefore not physically realizable . </P>

What are the dimensions of a baseball infield