Help with Calculus

4. For an object whose velocity in ft/sec is given by v(t) = -t2 + 6, what is its displacement, in feet, on the interval t = 0 to t = 3 secs? (4 points) 5' A girls throws a tennis ball straight into the air with a velocity of 64 feet/sec. If acceleration due to gravity is 32 ft/secz, how many seconds after it leaves the girl's hand will it take the ball to reach its highest point? Assume the position at time t = O is 0 feet. (4 points) 0 Cannot be determined 2' Find the velocity, v(t), for an object moving along the x-axis if the acceleration, a(t), is a(t) = 3t2 + cos(t) and v(O) = 2. (4 points) 0 v(t) = t3 + sin(t) + 2 O v(t) = t3 - sin(t) + 3 O v(t) = 6t - sin(t) + 2 O v(t) = t3 - 5in(t) + 2