Two cities X and Y are connected by a regular bus service with a bus leaving in either direction every T min. A girl is …

Two cities X and Y are connected by a regular bus service with a bus leaving in either direction every T min. A girl is driving scooty with a speed of \(60\mathrm{km}/\mathrm{h}\) in the direction X to Y notices that a bus goes past her every \(30\) minutes in the direction of her motion, and every \(10\) minutes in the opposite direction. Choose the correct option for the period T of the bus service and the speed (assumed constant) of the buses.