B.)<span>A doctor would use technetium-99m because a short half-life indicates a quick measurement, and a geologist would use rubidium-87 because a longer half-life means that there is a longer time to measure old rock. </span>
When children are small they are given vaccines that are usually dead viruses given to the body. These viruses don't cause damage to body and the body takes it as a real virus and prepare antibodies in the body but when a certain real disease or virus is in the body , the already presented antibodies fight with them for the protection of the body. These antibodies remain in the body so that when a disease or virus attacks the body the antibodies are already geared up to fight against them. Thus antibodies protect the body against invading microbes or viruses.
Answer:
The elements of the same group have the same number of valence electrons, that is why they have similar properties