Potassium-40 has a half life of 1.251×billion<span> years</span><span>. To determine the percentage potassium-40 remaining after 3.9 billion years, divide
3.9 by 1.251, = 3.12.
This is the number of times the original amount of potassium-40 reduces by 50%. The remaining percentage is therefore 100%/(3.12 * 2) = 16.03%.</span>
There are choices for this question namely:
<span>A) B cells produce IgE antibodies
B) B cells release cytokines
C) cytotoxic T cells present the class II MHC molecule-antigen complex on their surface
D) helper T cells release cytokines
The correct answer is "helper T cells release cytokines". Cytokines are released by helper T cells when B cells attach to them via receptors. These T cells "help" these B cells to differentiate by secreting certain cytokines. When B cells differentiate, they are converted to plasma cells and able to secrete antibodies to the antigen presented to the T cells. </span>
More often. please correct me if I am wrong
Knowing that she is already 75 years old, even though we don't know her health conditions, we can conclude that the vitamins might help her to avoid any deficiency related to minerals and vitamins, and it might also help her if she has an alimentary restriction meaning that she can't it a food that contains a needed vitamin or mineral.
Hope it helps,
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