Which detail from “John Glenn Interview” best supports the inference that the problems which occurred during the flight of Friendship 7 were unexpected? “‘Prior to your trip 50 years ago, there were unmanned U. S. rockets that exploded on the launch pads.’” “‘Well, there had been a number of failures but we weren’t going out to ride a failure.’” “‘But once you get on up there, then you're burned out - you're burning out your fuel as you go up and you're very light on fuel.’” “‘But the – there were some problems cropped up on the flight but was able to take care of those OK and – although they were things that we hadn’t really trained that much for.’”