a) Copper is at a higher temperature, so the flow of heat will take place from copper to iron. Heat is a form of energy, which always flows from higher temperature to lower temperature.
b) To determine the actual final temperature, the heat capacity of the calorimeter must be known. A calorimeter constant refers to a constant, which quantifies the heat capacity of a calorimeter. It may be determined by using a known amount of heat to the calorimeter and measuring the corresponding change in temperature of the calorimeter.
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Answer: B. Was twice as tall
Explanation: The strength of the gravitational force between two objects depends on two factors, mass and distance. If the distance is doubled, the force of gravity is one-fourth as strong as before.