By melting
Any added impurity can change the boiling point of a liquid.
it does not change
The pure ethanol has the boiling point 78.5 celsius while water has 100 celsius so when water is added to ethanol its boiling point becomes increased.
It increases.
YES
Salt
it does not change
it does not change
If you want to limit yourself to water only, you could change the pressure. That would greatly change the boiling point and slightly change the freezing point. If you don't care about limiting yourself to pure water, you can dissolve a salt or other substance in the water to lower the freezing point and raising the boiling point.
yes the boiling point changes with elevation. the higher the elevation the lower the boiling point.
No, the amount of water does not change the boiling or freezing point of water. The boiling point of water is always 100°C (212°F) at sea level, and the freezing point is always 0°C (32°F). The boiling and freezing points are determined by the chemical properties of water, not the amount of water present.
it does not change