Tech A says motor action occurs through the interaction of the magnetic fields of the field coils and the armature, which causes a rotational force to act on the armature, creating the turning motion. Tech B says two magnetic fields are required for motor action: one in the casing and the other in the rotating armature. Who is correct

Astone is thrown with a speed v0 and returns to earth, as the drawing shows. ignore friction and air resistance, and consider the initial and final locations of the stone. which one of the following correctly describes the change δpe in the gravitational potential energy and the change δke in the kinetic energy of the stone as it moves from its initial to its final location? options a.δpe = 0 j and δke = 0 j b.δpe is positive and δke is negative c.δpe = 0 j and δke is positive d.δpe is negative and δke is positive e.δpe = 0 j and δke is negative