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A biologist studied the population of ra...

A biologist studied the population of rats in a barn. He found that the average natality was 250, average mortality 240, immigration 20 and emigration 30. The net increase in populations is :

A

Zero

B

10

C

15

D

5

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The correct Answer is:
A
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PHYSICS WALLAH-ORGANISMS AND POPULATIONS -NEET PAST 10 YEARS QUESTIONS
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  6. Gause's principle of competitive exclusion states that:

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  10. Which of the following are likely to be present in deep sea water ?

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  11. A biologist studied the population of rats in a barn. He found that th...

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  14. Cuscuta is an example of :

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  15. Consider the following statements (a-d) each with one or two blanks: ...

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  16. The logistic population growth is expressed by the equation :

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  17. Considered the following four conditions (A-D) and select the correct ...

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  18. What type of human population is represented by the following are pyra...

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