An object initially at rest falls from a height h until it reaches the ground. two of the following energy bar charts represent the kinetic energy k and gravitational potential energy ug of the object-earth system at two positions. the first position is when the object is initially released, and the second position is when the object is halfway between its release point and the ground. which two charts could represent the mechanical energy of the object-earth system? select two answers. by ug k ug к mechanical energy at halfway point mechanical energy at release point mechanical energy at release point mechanical energy at halfway point d. c. к ug ug k mechanical energy at release point mechanical energy at halfway point mechanical energy at release point mechanical energy at halfway point