quang duong tu A den B dai 315km.1 o to xuat phat tu A luc 5gio10phut voi van toc la 52,5km/gio.hoi o to den tinh B luc may gio?biet doc duong o to nghi 30phut.
nhanh ho mk!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!