Answer:
a) ∆T=T1-T2
b) At the particle level the temperature changes are the result of the added energy causing the particles of water to move more vigorously. Either the particles of solid vibrate more vigorously about their fixed positions or the particles of liquid and gas move about their container more rapidly.
c) The state in which two substances in physical contact do not share any heat energy. The temperature of two substances in thermal equilibrium is said to be the same. Also see thermodynamics.
Explanation:
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