3. A circular track is divided into inner and outer loops with radii of 30 and 50 meters, respectively. Person A walks at constant speed on the inner loop, and person B runs at constant speed on the outer loop. It is known that for every one lap A completes, B completes exactly two laps. If A walks 45 meters, then during the same time period, B runs
(1) 90 meters
(2) 120 meters
(3) 135 meters
(4) 150 meters
(5) 180 meters