A stone is thrown upward from the top of a building at an angle of 30∘ to the horizontal and with an initial speed of 20.0 m/s. The point of release is 45.0 m above the ground. (a) How long does it take for the stone to hit the ground? (b) Find the stone's speed at impact. (c ) Find the range of the stone. (d) Write the displacement in vector notation: Δr→ = ? Group: How long does it take the stone to reach maximum height and what is its velocity (in unit vector notation) at maximum height?