So their are 60 min in an hour. you multiply 60 min times 6 (hours). you get 360 min. Then you divide that by 90 min and you get 4 Answer it orbits 4 times hope that helps
Please let me know if you want me to add an explanation as to why this is the answer. I can definitely do that, I just wouldn’t want to write it if you don’t want me to :)
