Answer:
13. is Option J) all of the above
and 14 I'm not completely sure but I think its option D.
Perhaps the answer is "physical characteristics". I am simply making an educated guess, however I do know early philosophers classified organisms into two groups, Plants and Animals, and identified them based on physical characteristics.
Detective= they uncover mysteries and understand how things happen by sampling blood and looking for clues
Answer: Wetlands, animal digestion, along with thermogenic sources such as oil and gas production.
Explanation:
Methane (CH4)
Methane comes from natural sources, such as wetlands and animal digestion, along with thermogenic sources, including oil and gas production. Natural gas is approximately 90% methane. Hope this helped!