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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

15

B

`05`

C

zero

D

10

Text Solution

Verified by Experts

The correct Answer is:
C
Net increase in population : (Natality + Immigration) - (Mortality + Emigration)
(250 + 20) - (240 + 30)
270 - 270 = 0
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