An astronaut on the moon.throws a baseball upward. The astronaut is 6 ft, 6 in. tall, and the initial velocity of the ball is 50 ft per sec. The height

s of the ball in feet is given by the equation s = - 2.7t +50t + 6.5, where t is the number of seconds after the ball was thrown. Complete parts a and b. a. After how many seconds is the ball 12 ft above the moon's surface? b. How many seconds will it take for the ball to hit the moon's surface?