Need geometry help Would really appreciate it been stuck on these pair questions !

Factor a^3 - 3 + 3a^2 - a. a) (a - 1)(a + 1)(a + 3) b) (a^2 + 1)(a - 3) c) (a^2 - 3)(a + 1)

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 =

If the altitude is drawn to the hypotenuse of a right triangle, then the two triangles formed are similar to the original triangle and to each other. which set of triangles shows the similar triangles created by the altitude in the diagram?