Part A )
the internal energy becomes twice.
Part B)
system loses heat Q = 1150 J
work done on the system = 480 J
change in internal energy U = Q + W
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= - 1150 + 480
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= - 670 J
change in internal energy U = - 670 J
Part C)
heat absorbed Q = 140 J
work done by the system = 85 J
internal energy change U = q + W
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= 140 - 85
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= 55 J
internal energy change U = 55 J
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