Arefracting telescope produces an image using

Objective lens

hope this helps :)

The refracting telescopes works on the same set of principle. The combination of objective lens present in the telescope helps to produce images. It has a combination of two lens (objective lens).

The eye piece is used to converge more lights than the human eye is able to converge on its own, it focuses it and then it present a bright, clear and magnified image of the object.

answer: 45

explanationyou have to add as well to be it could be

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.