Pleas help its timed

Imagine a new pasture with grass growing on it. every day after the seeds have germinated, the number of blades of grass in the pasture triples. after 18 days, the entire pasture is completely covered in grass. how many days did it take for the pasture to be one-third covered in grass?

An objects motion is described by the equation d= 4sin (pi t) what will the height of the object be at 1.75 seconds?

What statement is true? 2x^2-9x+2=-1