IA. If energy is being absorbed, then more hydrogen bonds are being broken. If energy is being released,more hydrogen bonds become fixed.
B. Durning melting, hydrogen bonds get broken and movement can occur. Durning freezing hydrogen bonds become fixed and water molecules can’t move as much
Explanation:

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Answer:
Extinction; the rat will stop responding to the song
Explanation:
Extinction will take place as the rat will stop responding to the song since no treats are being provided anymore.