A river that comes from rain, glaicers etc would be a good example of fresh water rivers. Cause the water is coming from something that is most likely been unthouched by man or has been filterd and cleaned from minerals in the ground.
Answer:
The periodic table of elements arranges all of the known chemical elements using this method. Elements are arranged from left to right and top to bottom in order of increasing atomic number. Order is usually according with the increasment (Is this a word?) of the atomic mass.
Explanation:
Have a good day :)
Oh this is easy.
Astronomy is the branch