The NET reproduction per individual per unit time (r) is per mouse per month in a population of 1,000 mice where 500 mice are born and 400 mice die monthly.

0.1

Explanation:

The Net Reproduction per individual per unit time (r) can be calculated as (births-deaths)/population size

Given that:

Population size of mice = 1,000; Birth = 500; Death = 400,

Net reproduction rate (r) = (births-deaths)/population size

r = (500 – 400)/1000

r = 100/1000

r = 0.1

The Net reproduction per individual per unit time (r) is 0.1

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