Explanation: For exploring mineral wealth mine surveying is used. Determining points of strategic importance is military surveying.

Explanation: Chain surveying is the type of surveying in which only linear measurements are made in the field. This type of surveying is suitable for surveys of small extent on open take simple details.

Explanation: Topographic surveying, Hydrographic surveying, Cadastral surveying classification is based on the nature of field survey. Traverse surveying, chain surveying is classified based on the type of instrument used.

Explanation: Compass surveying is not recommended for areas where the local attraction is suspected due to the presence of a magnetic substance.

Explanation: Compass surveying is recommended when the area is large, undulating and crowded with many details. It is not recommended for areas where the local attraction is suspected due to the presence of a magnetic substance.

Explanation: Dumpy level is used in levelling not in chain surveying. 20 m chain, arrows, pegs etc are mandatory for chain surveying.

Explanation: After having completed the preliminary work, the chaining may be started from the base line. The work in running a survey line is twofold, to chain the line and to locate the adjacent details.

Explanation: Theodolite is the most precise instrument designed for the measurement of horizontal and vertical angles. It has wide applicability in surveying such as laying off horizontal angles, locating points on line, prolonging survey lines, establishing grades etc.

Explanation: Generally, horizontal distances are measured by direct methods, i.e. laying of chains or tapes on the ground. These methods are not always convenient if the ground is undulating, rough, difficult and inaccessible. Under these circumstances, indirect methods are used to obtain distances. One such method is “Tacheometry”.

Explanation: Levelling is a branch of surveying is used to find the elevations of given points with respect to given or assumed datum.

Explanation: By working from whole to part, it is possible to eliminate the errors and to localise the errors. Otherwise, it might expand in magnitude.

Explanation: Though terrestrial photogrammetry is having accuracy in the obtained values, aerial photogrammetry is capable of producing precise output when compared to the remaining methods. This accuracy makes it different from the remaining methods and is recommended when high quality works are conducted.

Explanation: Hydrographic surveying can find its use in making nautical charts for navigation, making underground investigations for construction, establishing mean sea level, determining shore line etc.

Explanation: Direct ranging is done if both ends of surveying lines are visible. Indirect ranging is done when both ends are not intervisible.

Explanation: Three principal methods are used for determining a difference in elevation, namely, barometric levelling, trigonometric levelling and spirit levelling. Traversing is that type of surveying in which a number of connected survey lines form the framework.

Explanation: The type of surveying in which the mean surface of the earth is considered as a plane and the spheroidal shape is neglected is plane surveying.

Explanation: Depending on the instruments used in determining the relative directions of the traverse lines. The principal methods adopted are Chain traversing, Compass traversing, Transit tape traversing, Plane-table traversing. Tacheometric surveying involves a lot of instrumental work rather than ground work.

Explanation: The methods which are adopted in case of plane table surveying involve radiation, Intersection, resection and traversing, which are used based on the type of output required.