A map of Nelson County is laid out in the standard (x,y) coordinate plane below, where the center of the county is at (0,0). a cell phone tower is at (5,4) and Esteban's house is at (10,-2). each coordinate unit represents 1 mile. the tower signal range is 10 miles in all directions. how much land area to the nearest 10 miles does the tower signal range cover? a=80^2 b=100^2 c=310^2 d=400^2