JUPITER17 AND EVERYBODY THAT COMMENTED ON MY POST IS A BULLY!!

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?

If f(x) = x+8 and g(x) = 4x- 3, find (f+g)(x)

In the diagram of circle o, what is the measure of zabc?