How many people are invited to take part in the experiment? [br] [originaltext]

Listening to music while you drive can improve your speed and ability to get away from accidents, according to Australian psychologists. But turning your car radio up to full volume could probably make you end up in an accident. The performance of difficult tasks can be affected if people are subjected to loud noise. The experience of pulling up at traffic lights alongside care with loud music made some psychologists in the University of Sydney look into whether loud music has something to do with driving.     The psychologists invited 60 men and women aged between 20 and 28 as subjects and tested them on almost the same driving tasks under three noise conditions: silence, rock music played at a 55 decibels, and the same music at 85 decibels.
    For 10 minutes the subjects sat in front of a screen operating a simple machine like a car. On the tracking task, there was no difference in performance under the three noise conditions. But under both the loud and quiet music conditions, the performers "braked" at a red light about 50 milliseconds sooner than they did when there was no rock music at all. That could mean a reduction in braking distance of a couple of meters actually, the difference between life and death for a pedestrian.