48) Which term is used for representing surface of the earth on a small scale in surveying?

49) Which method of surveying the area is sub divided into network of triangles?

50) Which survey deals with the collection of the details of cyclonic affected area, flooded area etc, is done by aeroplane in air?

51) Which survey deals with the star's in the sky?

52) Which survey deals with the determination of natural & artificial features on the earth?