Answer:
A. 3s
Step-by-step explanation:
The height of the object after t seconds is given by:

When will the object hit the ground?
It hits the ground after t seconds, and t is found when
. So







3 seconds, so the correct answer is given by option a.
A graphing calculator working the quadratic regression problem for these three points gives the equation as
y = 2x² +7x -5
Never,because obtuse angle is an angle measuring between 90 and 180
and if an angle measures 180 then it is a straight angle