I know that the answer is D, but why would it be D

Apopulation has 1000 individuals. over a period of 1 year, 500 newindividuals are born. which equation shows how to calculate the birthrate ofthis population? a. 500 - 1000 = 0.5b. 1000 x 0.5 = 500c. 1000 - 500 = 2d. 1000 + 500 = 1500

How does upwelling affect coastal fisheries? upwelling damages nutrient supplies at coastal fisheries as the warm, nutrient-rich surface water is replaced by nutrient-poor, cold water. upwelling damages nutrient supplies at coastal fisheries as the cold, nutrient-rich surface water is replaced by nutrient-poor, warm water. upwelling improves the nutrient supply at coastal fisheries as the warm, nutrient-rich surface water replaces the nutrient-poor, cold water. upwelling improves the nutrient supply at coastal fisheries as cold, nutrient-rich water replaces the warm, nutrient-poor surface water.

Select the correct answer from each drop-down menu proteins are