B) If 15 kJ of energy output occurs after an input of 55 kJ, what is the efficiency?

we can conclude that the melting point of table salt is above room temperature (it's actually 801 deg c). the melting point of mercury must be below room temperature (- 39 deg c).

answer by yourhope:

how do models compare to real-world objects?

d. most models represent a real-world object in a simpler way.

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