Answer:
your answer would be : examples such as Thallium-206, Lead-210, & Bismuth-214.
Using scientific reasoning
Answer: 6.6
Explanation: For steps pleaase go here https://www.percentagecal.com/answer/what-is-15-percent-of-44
The answer for the first question would be water. It is the substance that is a compound since it is made up of different elements. For the second item, i think the best answer is phosphorus and nitrogen. They are the limiting nutrients. For the last item, the correct answer is reservoirs.