I believe blood vessels constrict
A. There are 4 codons
Idk B
Answer:
francium
Explanation:
The most expensive natural element is francium, but it decays so quickly it can't be collected to be sold.
Compound- a new substance formed by the combination of two or more different atoms
Energy Level- area that electrons are found around an atomic nucleus
Element- a substance consisting of only one type of atom
Molecule- the smallest complete form of a compound or diatomic gas
