A projectile is launched from ground level at an angle of 50.0 degrees above the horizontal with a speed of 30.0 m/s. If the projectile is moving over level ground, how long is it in the air before it again contacts the ground

A10-kg piece of aluminum sits at the bottom of a lake, right next to a 10-kg piece of lead, which is much denser than aluminum. which one has the greater buoyant force on it? explain. b - the aluminum a) both have the same buoyant force. b) the aluminum c) the lead d) it cannot be determined without knowing their volumes.