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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>
Answer: principle of neuroplasticity.
In the result of the brain damage, amir stopped moving the left side of his body and after rehabilitation <span>he partially regained its functions. Why? because of</span> neuroplasticity. The brain, especially in children, has the ability of being plastic, meaning that the brain activity
associated with a given function, can be transferred to a different
location. This process is achievable through rehabilitation.