Answer: you tell what to fill inside the blanks lolololol
Explanation: i dont have one
B. Sunlight doesn't reach the bottom of lakes..
B - energy flow from one tropic level to the next
Experiments in general are more reliable when a greater sample size is used. When using a small sample size, a mistake or fluke can greatly effect the outcome of the experiment. With a large sample size, there is more data to understand averages and deviations to the average data. The average will likely be more accurate with more data, which would make his sample size more reliable.
I am thinking it is by heating themselves in sunlight. I think this because when I bring lizards to mind, they are cold blooded, and they need sunlight to bath in so they do not start to lack warmth to live.
I hope this helps.