Which statements are true about point and nonpoint source pollution? human activity causes point and nonpoint source pollution. only nonpoint source pollution affects abiotic factors in a watershed. point source pollution affects only the part of the lake or river near it. both point and nonpoint source pollution affect biotic factors in a watershed. point pollution flows through the bodies of water in a watershed but not through its land.

Both point source pollution and non-point source pollution affect biotic factors in a watershed.

Explanation:

Point source pollution is the "single identifiable source" from which the pollutants arise. They can be pipe, factory, ship etc. Few factories discharge the pollutants directly into the water bodies. Few of them treat it first and then discharge to the sewage plants.  Nonpoint source pollution results from "land runoff, drainage, atmospheric deposition". After the runoff, the human made pollutants and natural ones will get deposited into wet lands, lakes and ground waters.  

The introduction of dangerous items into the environment is referred to as pollution. Pollutants are the term for these dangerous compounds.

Statements (i) or (a) and (iv) or (d) are true about the sources of non-point and point pollution.

The Environmental Protection Agency (EPA) of the United States defines:

1. Point source pollution (PSP) is any contaminant that enters the environment from a restricted and easily identifiable source.

Sources:
Oil refineries, paper, and pulp mills, chemicals, Sewage treatment plants, vehicles, electronics or technological manufacturers, and factories are all examples of PSP.

2. Nonpoint-source (NPS) pollution is the polar opposite of point-source pollution in that contaminants are spread out over a large area.

Sources:
snowmelt or rainfall moving over and through the earth causes NPS contamination.
As the runoff progresses, it takes up and transports contaminants, both natural and man-made, eventually depositing them in lakes, rivers, wetlands, coastal waterways, and groundwater.

Therefore,  Point and nonpoint source pollution are both caused by human activities, and both have an impact on biotic variables in a watershed. This proves that statements (i) and (iv) are the right sources of responses.

For more information about pollution, refer to the link below:

link

Hi ur litt it's pretty cool that i get points for just rambdomly answering stuff

This is all you, but i can give you some topics that you could try. if it rained when you want to do something outdoors, it 'limits' that human activity. maybe you want to do an experiment that goes throughout the whole year and you have to have above freezing the entire year. this 'limits' your activity. i thought of those just off of the top of my head. something that gets to me that might be getting to you is you are thinking too hard about what to do. think simply, and if it is too simple, then bump it up just a little bit.