12C,13C,14C
these are all carbon Isotopes
<span>The four biological macromolecules are carbohydrates, lipids, proteins and nucleic acid. These macromolecules are known as polymers and are built when monomers join together by a process known as the dehydration reaction. The dehydration reaction is a chemical reaction that produces water (H2O) and the result is the covalent bonding of the two monomer molecules. The monomer molecules consist of nutrients found in the soil, as in the case of plants, and the intake of food as in the case of animals.
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Answer:
The last one if there are multiple answers please tell me.
Explanation:
just when with the one i knew in heart
Im not sure but if you think of it, the one that you didn't put any salt is a independent variable because it doesn't really rely on anything it doesn't have salt. The Dependent variable would be the 2nd and the 3rd cup because it doesn't have much salt but the 4th cup has lots of salt so its basically controlled. Hope it helps !