The flight path of a rocket, launched from the ground, is modeled by y = 0.25(60x-x2), where y is the height of the rocket in meters from the ground and x is the time in seconds after it was launched. Find the vertex of the parabola and explain what it represents in terms of the context. (30, 225); rocket reaches maximum height of 225 feet after 30 seconds (60, 0); rocket lands at 0 feet after 60 seconds O(30, 225); rocket reaches maximum height of 30 feet after 225 seconds (60, 0); rocket reaches 60 feet after 0 seconds