In her math class, Elena has been learning about how to use the identity property of multiplication with fractions. She is still a little confused. She wants to write a fraction as one whole. She wrote and which is correct? How do you know?

Which expression is equivalent to the expression shown?

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 =

Can someone me out here and the tell me the greatest common factor