What step of the carbon cycle occurs when soil bacteria return carbon dioxide, methane, and other carbon compounds to the atmosphere? a) fossil fuel formation b) decomposition c) assimilation d) carbon fixaiton

Vaccines are weakened forms of disease causing microorganisms, which are given to patients to prevent disease. after the vaccine is administered, the immune system responds by creating a(n) to recognize the a.) antibody, antibiotic b.) antigen, antibody c.)antibiotic, antibody d.)antibody, antigen