To calculate the velocity on an object, the of the position vs time graph should be calculated

Slope of graph

Explanation:

The total displacement divided by total time taken by an object is called its velocity. When a position - time (x-t) graph is plotted, the magnitude of velocity is given by its slope.

The slope of position-time graph gives the velocity of an object. The attached figure shows a position time graph.

The slope of this graph is given by :

i.e.

The velocity of this object is 10 m/s. So, to calculate the velocity on an object, the slope of the position vs time graph should be calculated.                              

what is the statement?

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.