Answer:
A feature of the reduction in death rates has been the increased excess mortality of males. There have also been big and rapid reductions in death rates in many developing countries, even in the absence of important improvements in living standards. Antibiotics and insecticides have made a major contribution to this movement in the last twenty years. It is unlikely that death rates will fall as rapidly in the next few decades as in the recent past in either developed or developing countries.
The rate of natural increase refers to the difference between the number of live births and the number of deaths occurring in a year, divided by the mid-year population of that year, multiplied by a factor (usually 1,000). It is equal to the difference between the crude birth rate and the crude death rate.
Based on the knowledge about radioactive elements, the decay of radioactive elements such as uranium creates heat especially in Earth's crust, where these elements are abundant.
<h3>What are radioactive elements?</h3>
Radioactive elements are elements which undergo spontaneous decay of their nucleus and in the process produce elements with smaller atomic masses with the release of radiation and heat.
Examples of radioactive elements include uranium and radium.
Therefore, the decay of radioactive elements such as uranium creates heat especially in Earth's crust, where these elements are abundant.
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