60 years is three half life for the substance, so 40*1/2^3=5
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the answer is
A.the ability of your heart and lungs to work during prolonged exercise
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SAVAGELEGEND72
Answer:
Adaptive defenses include both humoral and cellular immunity.
Explanation:
The innate immune response is the non-specific immune response and serves to provide an immediate and general immune response. The adaptive immune responses are the specific immune responses. Adaptive immune responses include cell-mediated immunity and antibody-mediated immunity.
Cell-mediated immunity includes T cells (cytotoxic and helper T cells) while antibody-mediated immunity includes the production of antibodies from B cells. Binding of antigen to B cells is followed by their transformation into plasma cells and produce antibodies. Some of the activated B cells form memory B cells that are responsible for quicker and strong secondary immune responses.
The force between them if the distance between them is doubled is a. F/4
Explanation:
- To find the answer, we can use Coulomb's law where it is defined as the force between two point charges is directly proportional to the magnitude of the point charges and proportional inversely to the distance between them.
- The equation can be written as,
where k is the Coulomb constant, 
are the point charges, and r is the distance between these two point charges. - To find the answer to this question, just substitute 2r in the place of r hence, you will get
as the new force when the distance is doubled.
