Answer:
1) a 2)b
Explanation:
reasons
1) Once carbon dioxide dissolves in water, it reacts with water molecules to form carbonic acid.
2) the burning of fossil fuels like coal and oil has increased the concentration of atmospheric carbon dioxide (CO2). This happens because the coal or oil burning process combines carbon with oxygen in the air to make CO2.
Rhinoviruses and herpes simplex are just two common viruses out of the other thousands of them that the immune system has to protect the body against.
