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>
Eutrophication occurs due to the increased concentration of natural nutrients. Conversely, artificial eutrophication happens due to human activities.
<h3>Eutrophication and artificial eutrophication</h3>
Eutrophication is a biological phenomenon that occurs due to the increased concentration of natural nutrients such as algae in a water body.
Artificial eutrophication is a specific type of eutrophication process caused by human activities.
Artificial eutrophication can be caused, for example, for an excessive overload of fertilizers in a lake.
Learn more about eutrophication here:
brainly.com/question/8499582
Answer:
Heart attack
Explanation:
Heart attack is the death of a part of heart muscles and severe pain that causes heart constriction having pain in the chest which spread to the left shoulder and down the arm thereby causing the feeling of pressure in the chest.
This is caused when a blood clots blocks blood flow to the heart thereby leading makes the tissue to loss oxygen and die.
The symptom of heart attack are;
pain in the chest, neck, back or arms, fatigue, lightheadedness, abnormal heartbeat and anxiety, nausea.
Treatment ranges from surgery, medication , rehabilitation e.t.c.