Since 1915, chemical fertilizer has been mass produced for farming. which of the following is the main water pollution problem caused by chemical fertilizer? increased carbon monoxide radioactive substances in the water increased nitrate and phosphate levels higher levels of bacteria, viruses, and protozoa

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.

it would be b. 6co2 + 6h2o --> c6h12o6 + 6o2