Answer: Option (c) is the correct answer.
Explanation:
A long hydrocarbon chain that consists a terminal carboxylic group is known as a fatty acid.
An unsaturated fatty acid consists a double bond within the fatty acid chain. If a fatty acid contains more than one double bond then it is known as polyunsaturated fatty acid.
For example, oelic acid has chemical formula 
is an unsaturated fatty acid.
Therefore, we can conclude that option (c) represents an unsaturated fatty acid.
Answer:
Graptolites lived from the Cambrian Period, about 510 million years ago, disappearing in the Carboniferous Period, around 320 million years ago.
hope this helps!
Answer:
As the volume of available water increases, the rate of decomposition also increases. Many decomposers secrete enzymes onto decaying matter and then absorb any dissolved molecules and sunlight allows things to grow out of decomposers allowing faster decomposition from the plant absorbing the other nutrients from the things in the decomposer making the soil rich and fertile.
