WeBWorK Standalone Renderer

From a clifftop over the ocean ${160\ {\rm m}}$ above sea level, an object was shot straight up into the air with an initial vertical speed of ${137.2\ {\textstyle\frac{\rm\mathstrut m}{\rm\mathstrut s}}}$ . On its way down it missed the cliff and fell into the ocean. Its height (above sea level) as time passes can be modeled by the quadratic function $f$ , where $f(t)={-4.9t^{2}+137.2t+160}$ . Here $t$ represents the number of seconds since the object’s release, and $f(t)$ represents the object’s height (above sea level) in meters.

1) After , this object reached its maximum height of .

2) This object flew for before it landed in the ocean.

3) This object was above sea level ${6\ {\rm s}}$ after its release.

4) This object was ${1076.3\ {\rm m}}$ above sea level twice: once after its release, and again later after its release.

(Use m for meters, and s for seconds.)

You can earn partial credit on this problem.