Chemical because the propane has stored chemical energy which is being released and a by-product of that propane is heat or themal energy.
Scientific method
Explanation:
The scientific method is the name of the process scientists use to gain knowledge about the physical world.
The scientific method is a systematic approach into the study of nature. It follows the following processes:
- Detailed observation
- Asking of question
- Formulation of hypothesis
- Experimentation
- Analysis and interpretation
- Conclusion
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Experiment brainly.com/question/1621519
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