A catalyst decreases the activation energy and increases reaction rate that is needed.
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>
Explanation:
But researchers in Israel have done a study showing that families have characteristic facial expressions, ones even shared by blind members of the families. The results suggests that such expressions may be inherited and thus under some genetic control.
