Im not really good with essays,but i can give you an idea.
I think the best way to learn things is to find an interest in it and continue doing some research on it until you have a good understanding of it.Thing like a new sport or experiment
The zebra mussels in the great lakes are an invasive species. They eat the food for fish and other animals which could cause their starvation and could interfere with the present food web and pyramids. They also can cause vegetation to increase in growth rapidly.
Fundamental principle is the answer to the question
The correct answer for the question that is being presented above is this one: "salt." <span>One of the most valuable items traded in North Africa long ago was salt. Salt was abundant at that time, and thus North Africa is taking advantage over it.</span>
Gamma ray photons carry more energy than photons of any other wavelength.
You can't actually use the illustration to answer the question, because it doesn't say anything anywhere about energy. Still, i'm glad that you did include the illustration, and that i was able to see it, and now I can give you even more help: The illustration has several problems and outright errors. Don't spend too much time trying to learn stuff from it.