put this in your own words. 12 points on the
global warming refers to a change in the earth's climate that is causing it to heat up. the greenhouse effect, on the other hand, is a natural process that happens constantly, due to sunlight and the atmosphere.

Global warming is a change in the earth's climate which makes it heat up. While the greenhouse effect is a natural process that always is happening because of sunlight and the atmosphere.

I hope this is easy enough.

estuaries are the partially enclosed coastal bodies of brackish water formed at the mouth of sea where river meets an ocean. it is a transition zone between river and sea water so estuaries are influenced to both marine environment such as tides, waves and to riverine such as flow of fresh water and sediments. the mixing of sea and fresh water provide high level of nutrients, making estuaries a high product habitats.

many estuaries suffers degradation from a variety of human activities like erosion from deforestation, overgrazing, overfishing, drainage and eutrophication.

so from the above statement answers will be

1. false as estuaries are formed due to both brackish and freshwater.

2.true, due to high productivity estuaries are breeding ground for many marine species.

3. direct and indirect activities of man that contribute to pollution and deposition of sediments.