Answer
(a) $(90,0)$, $(90, 90)$, $(0, 90)$
(b) $232.43$ ft
(c) $366.2$ ft
Work Step by Step
(a) Coordinates of the 1st base would have a y-coordinate of 0 as it lies on the x-axis of the grid. The x-coordinate would then be 90 as the distance from the home plate(the origin, (0,0)) to the 1st base is 90 ft.
1st Base = $(90, 0)$
3rd base would have a x-coordinate of 0 as it lies on the y-axis of the grid, and it would have a y-coordinate of 90, as it lies 90 ft away from the home plate. So;
3rd base = $(0, 90)$
2nd base has the same y-coordinate as the 3rd base, and the same x-coordinate as the 1st base, so:
2nd base = $(90, 90)$
(b) 2nd base = $(90, 90)$ , Right fielder = $(310, 15)$
Distance = $\sqrt {(310-90)^2+(15-90)^2}$
=$\sqrt {54025}$ = $232.43$ ft
(c) 3rd base = $(0, 90)$, centre fielder= $(300, 300)$
Distance = $\sqrt {(300-0)^2+(300-90)^2}$
= $\sqrt {134100}$ = $366.2$ ft