Answer:
In chemistry, a radical is an atom, molecule, or ion that has an unpaired valence electron. With some exceptions, these unpaired electrons make radicals highly chemically reactive. Many radicals spontaneously dimerize. Most organic radicals have short lifetimes. so D
Explanation:
The blood going out from the arteries is full of oxgyen.It delievers that oxgyen to organs,therefore when it returns in the veins it contains carbon dioxide.
OSHA (one part of a Personal Fall Arrest System) requires workers to wear a full-body harness, when they are working on a suspended scaffold more than 10 feet above the working surface, or when they are working in bucket truck or aerial lift.
