The birth rate is defined as the number of births in a particular time divided by the total population. So the correct option is A.
A total number of births in a specific time (a year) divided by the total population (usually taken as 1000) is called the birthrate. The birth rate is calculated for various reasons.
Some of the things for which birth rate is needed are population count, universal registration of births etc.
Population growth is calculated using birth rate, mortality rate and migration rate from a population. The mid-year population is usually taken as the estimated population.
The birth rate is also referred to as natality. The rate of natural increase is given when the crude death rate is subtracted from the crude birth rate.
The birth rate of a population should be maintained at a moderate level by providing resources to people with children, creating awareness about methods of contraception etc.
The birth rate is calculated by dividing the number of births by the total population.
Therefore the correct option is A.
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Trees are a crucial part of the carbon cycle, a global process in which carbon dioxide constantly circulates through the atmosphere into organism and back again. Carbon is the second most valuable element to life, you know, after water. Anyway, trees take carbon from the atmosphere through photosynthesis in order to make energy. This carbon is then either transferred into oxygen and released into the air by respiration or is stored inside the trees until they decompose into the soil. Therefore, the absence of trees would result in significantly HIGHER amounts of carbon dioxide in the air and LOWER amounts of oxygen! The filthy air would also be full of airborne particles andpollutants like carbon monoxide, sulfur dioxide and nitrogen dioxide and its temperature may increase by up to 12 F.
the phase that follows after metaphase is anaphase
Mouse needs care from its parents after birth. So, the correct option is (C).
Mammals are a group of vertebrates in which the young are nourished by the milk of the special mammary glands of the mother. Mammals are distinguished by many other unique features such as hair being a typical mammalian feature but in some mammals such as whales, it has disappeared except in the embryonic stage.
The lower jaw of mammals is attached directly to the skull, rather than to a separate bone called the quadrilateral, as in all other vertebrates. A series of three small bones conduct sound waves to the middle ear while the muscular diaphragm separates the heart and lungs from the abdominal cavity.
Mature red blood cells (erythrocytes) in all mammals lack a nucleus, while all other vertebrates have red blood cells. All of them require care from parents after birth.
Thus, Mouse needs care from its parents after birth. So, the correct option is (C).
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