to make it even more egregious:
"Quick! Climb to about 1000 feet above sea level and the trex will boil and we will be safe!"
"Quick! Climb to about 1000 feet above sea level and the trex will boil and we will be safe!"
"climb to FL20 and the flying dinosaur thing will break" could work though
Since, annoyingly, international altitudes are done in increments of 1000 feet (ish, handwaving)