A toy plane has a mass of 2.5 kg and is 18 m above the ground. It is moving at 4.5 m/s.

The toy plane’s total mechanical energy is the sum of its gravitational potential energy and kinetic energy. Using g = 9.8 m/s², its potential energy is 2.5 × 9.8 × 18 = 441 J, and its kinetic energy is ½ × 2.5 × 4.5² ≈ 25.3 J. The total is about 466 J, so the correct choice is C, 466 J.

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