Lawn and farming fertilizer is harmful to the enviroment due to the abundance of chemicals. When it rain or seeped underground, the fertilizer leaked into the nearby lake and thus, all the fish died to the chemicals in the fertilizer.
Blood
Blood is the transport fluid circulating in the body and is responsible for the transport of substances from one point to another. Blood is composed of red blood cells, white blood cells, platelets and plasma. All of these components work together and transport substances such as oxygen, glucose and amino acids to the cells and remove waste substances such as carbon dioxide and urea away from the cells.
They are offered to students based on their GPAs; one way of measuring merit in schools. Merit-based scholarships help school children out of worse economic environments where money is not abundant to gain a opportunity to get into a good college based on their good grades.
If lots of things were changed (independent variable) then you wouldn’t know what caused the trend(s) in your results so you have to control all but one variable so you know that you are just changing the one thing so that is the only thing that could cause the trend. I hope that made sense
