In order to change a solid to a liquid or a liquid to a gas, what is needed? A high boiling point
An increase in thermal energy
A high melting point
A decrease in thermal energy
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increase in thermal heat

explanation: In order to change the state, more energy is needed.
When you want to go from a lower state (solid) to a higher state (liquid) then you need more energy. and more energy means more heat in this case. if it was going from liquid to solid, you would need less thermal energy.