Copper is a better conductor.
We can solve this problem using the law of conservation of energy.
This law states that energy in a closed system must stay same.
That means that the energy of a ball leaving the hand and the energy of a ball when it reaches its maximum height must be the same.
The energy of a ball leaving the players hand is kinetic energy:

The energy when the ball reaches its maximum height ( and has zero velocity) is potential energy in a gravitational field:

As said before these energies must be the same, and that allows us to find the initial speed:

When we plug in all the number we get that
Answer:absorbs and emits electromagnetic radiation at all wavelengths
Explanation:
A blackbody is a believed to be a perfect absorber and reflector of radiation. Blackbody, in physics, refers to a surface that absorbs all radiant energy that falls on it. It is supposed that because incident visible light will be absorbed rather than reflected, the surface will appear black.
Answer:
Spiral Galaxy
Explanation:
Spiral galaxies are named by their spiral structures that extend from the center into the galactic disc. The spiral arms are sites of ongoing star formation and are brighter than the surrounding disc because of the young, hot OB stars that inhabit them.