Respuesta :

irspow
A=(απr^2)/360=(απd^2)/1440   (r^2=d^2/4)

α=1440A/(πd^2)

s=απd/360  (where s=arc length) so

s=(1440Aπd)/(360πd^2)

s=4A/d and since A=10mi^2 and d=20mi

s=(4*10)/20

s=2 miles