4. A projectile is launched directly upward with initial speed 17 can have height modeled by h(t) = vt g'ztz a) At what time will the projectile fall to the ground? Your answer will be in terms of 1:. b) Find h'(t). c) Find the value of t so that h'(t) = 0. d) Let 1: = 10 meters] sec. Over what time interval does the object have positive (upward) velocity? What time interval does the object have negative (downward) velocity? e) Assuming Let I: = 10 meters/ sec, what is the maximum height of the project