The answer to that question is c
The major force between ethanol and rubbing alcohol is hydrogen bond. Hydrogen bond are intermolecular force that are weaker than covalent bond but holds atoms together in a molecules. For an hydrogen bond to be formed, a molecule must contain an hydrogen atom that will be bonded to one of the most electronegative element.
I've prepared some analysis and <span>cucumbers do have many comparable properties to potatoes, tomatoes, and lemons, all of which I know do work. So I would presume that cucumbers would also work. I would recommend trying it yourself to perceive. I'd love to hear the outcomes of your experiment. ;) </span>
Answer:
5 mg
Explanation:
If one half life is 4 hours, then 3 half lives is 12 hours.
This means that the sample will decay to 1/8 of its original amount.
So, the answer is 40(1/8) = 5 mg.