The one change that is made by the scientist is called the

(a) The whole structure is made up of stone and marble with

each of them having engraved astronomical scale. It consists of fourteen geometric

devices, used for measuring time, forecasting weather changes, predicting behaviour of planets

and finding extraterrestrial altitudes which attracts architects, historians and scientists

from all over the world.

(b) Iantar Mantar was built by Maharaja Sawai Jai Singh-II

of Jaipur in 1710 AD. Jantar Mantar finally got the status of a national monument in

1948.

(c) Maharaja Jai Singh was a fanatical astronomer who felt

that the tables used by pundits were deceptive and the actual planetary changes and

predictions of eclipses would not be possible through these measuring parameters. He wanted an

improved and efficient means through which exact predictions could be made. So, he

gave shape to such an instrument.

(d) Iantar Mantar consists of 14 geometric devices which are

fixed and point to a specific direction. The largest device or instrument is the ’Samrat

Iantar’ which is 90 feet high and its shadow is plotted in such a manner that it shows the

exact time of the day. 

(e) (i) ancient 

(ii) devices

(iii) perception 

(iv) astronomical

(Hope this helps)