PLz hep me with this qustion

Add the fractions, and simply the result to lowest terms. 2/3 + 2/7= ?

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?

John checked his watch and said that it is thursday, 7 am. what will the day and time be 2006 hours plzzz i will give you 100 points