WAEC Biology 2019 Papers

Concept:Population density is the number of organisms present in one unit area of a given habitat.Explanation:The formula used to calculate population density is: $\text{Population density} = \frac{\text{Number of organisms}}{\text{Area}}$.In this case, the number of ants is $90$ and the total area of the field is $100 \, \text{m}^2$.Substitute the given values into the formula:$\text{Population density} = \frac{90}{100}$.Simplifying the fraction yields:$\text{Population density} = 0.90$.This means there are $0.90$ ants per square metre of the field.The correct option that matches this calculated value is B.Answer:B. 0.90