Please help me it’s due in a little bit and i’m struggling with it

What could explain what happened when the time was equal to 120 minutes

Astuntman jumping off a 20-m-high building is modeled by the equation h=20-5t^2, where t is the same in seconds. a high-speed camera is ready to film him between 15m and 10m above the ground. for which interval of time should the camera film him?

1.two more than the quotient of a number and 6 is equal to 7 use the c for the unknown number translate the sentence into an equation