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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

Text Solution

Verified by Experts

The correct Answer is:
A
Net increase in population = Average natality + Immigration – Average mortality – Emigration
= 250 + 20 – 240 – 30
= 270 – 270 = 0.
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