An obstacle course for an endurance competition is set up such that only 50% of the competitors who start the race do not make it past the first obstacle. of those who do, 65% make it past the second obstacle. the final obstacle is the toughest and only one third of those who complete the second obstacle are able to get past the third obstacle and finish the race. if 13 people finish the race, how many contestants started the race? 60 66 90 120 144