Energy added to a cyclical heat engine
a. is completely converted to external work.
b. is converted to increased internal energy in the engine plus external work.
c. is used to generate work that is greater than the added energy.
d. is converted to work and to waste heat.

D. is converted to work and to waste heat.

Explanation:

A cyclical heat engine first gets provided energy by another source, which once provided is turned into work inside the engine causing the engine to move/run. Afterwards the heat inside the engine is expelled so the process can repeat itself. Therefore the answer to this question is D. is converted to work and to waste heat.

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