Final answer:
The mechanical energy of the apple is 8.7 joules, which is the sum of its kinetic energy and potential energy. ;
The mechanical energy of the apple is 8.7 joules, which is calculated by adding its kinetic energy of 5.2 joules to its potential energy of 3.5 joules. This total reflects the combined energy due to the apple's motion and position. Understanding mechanical energy is fundamental in physics as it demonstrates energy conservation within a system.
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