Ajuggler is performing her act using several balls. she throws the balls up at an initial height of 4 feet, with a speed of 15 feet per second. if the juggler doesn't catch one of the balls, about how long does it take the ball to hit the floor?

hint: use h(t) = −16t2 + vt + s.

Sanya noticed that the temperature was falling at a steady rate of 1.4 degrees every hour from the time that she first checked her outdoor thermometer. by 6 a.m., the temperature had fallen 21 degrees. which expression can you use to find how many hours earlier she had first checked the thermometer?