Of the people in Kurt's apartment building, 10 have a jacket with a hood and 10 have a jacket with buttons. 6 people have a jacket with both a hood and buttons. How many people have a jacket with a hood or buttons or both?

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?

Does the point (1, sqrt 7) lie on circle shown.

The function models the number of accidents