Question

part of the pathway of energy through ecosystems is as follows light → chemical → mechanical. what is the last pathway for energy? water heat air

Explanation:

In ecosystems, energy flow follows the law of energy transformation. Light energy is converted to chemical energy (e.g., in photosynthesis), then to mechanical energy (e.g., in organism movement). Eventually, energy is dissipated as heat due to the second law of thermodynamics (energy tends to disperse as heat in energy transfers). Water and air are not energy forms but substances, so heat is the final energy pathway.

Answer:

B. heat