According to the second law of thermodynamics, heat energy released by an organism is gone forever used by another animal released into the environment and unusable absorbed by plants for photosynthesis

According to the second law of thermodynamics, heat energy released by an organism is released into the environment and unusable. This energy is also known as entropy which is defined as the tendency of things to be dispersed and spontaneous. This means that entropy is always random and becomes unavailable energy.

The the passage this question was provided for, you may find the fallowing text: "When a process converts energy from one form to another, some energy converts into heat, a less usable form that disperses into the environment."

Released into the environment and unstable.

This stiffening process, called Rigor Mortis, has a roughly known time of occurrence and can therefore be used to estimate time of death. In general: If the body feels warm and no rigor is present, death occurred under 3 hours before. If the body feels warm and stiff, death occurred 3-8 hours earlier.