An amplifier.
Electrical energy provided to an amplifier is converted into sound energy as it is "fed" or provided to the speaker portion of an amplifier.
Never too early to start searching. Do some research about student savings versus parent savings though. If a student has savings, they will make you use it to pay for college, while the same amount of savings in the parents name may be exempt. Check it out.
True.
A zero on the Kelvin temperature scale is also know as Absolute Zero because that is when the atom(s) have literally no kinetic energy.