A 20-kilogram concrete block is dropped from the top of a tall building near a construction site. The block has fallen a distance of 50 meters and has a speed of 28 meters per second when it hits the ground. Calculate the work done by friction by the block as it fell.

answer would be letter choice (a),   a ball resting on a shelf. would be another example of potential energy   >   stored energy > not moving.

a ball spinning on a finger   >   kinetic energy > moving energy

a ball rolling on the ground   >   kinetic energy   > moving energy

a   ball flying through the air   > kinetic energy   >   moving energy

hope that                                         : )

ok

explanation:

answer///terminator or twilight zone;

part 1: which substance has a higher solubility?

a

smallest amount left undissolved atall temps in table shown most has dissolved high sol'by