Need help on this equation please!!

Aball is thrown from a height of 139 feet with an initial downward velocity of 15 ft/s. the ball's height h (in feet) after t seconds is given by the following. h=139-15t-16t^2 how long after the ball is thrown does it hit the ground? round your answer(s) to the nearest hundredth. (if there is more than one answer, use the "or" button.) t =

Write a fraction less than 1, which has a denominator of 6 and is greater than 3/4 plz answer !

Write the expression 7x^3-28xy^2 as the product of 3 factors