The length between two points on a topographical map is 5m. What is the actual distance between them if the scale of the map is 1:50000?

A. 2.5 km

B. 3.0 km

C. 3.5

D. 5.0

Chain survey is most convenient for measurements on ?

A. rocky environment

B. plains

C. embarkment

D. irregular slopes

Th earth's crust consists essentially of?

A. magnesium and silica

B. silica and aluminium

C. calcium and aluminium

D. magensium and calcium

The rock type formed through the deposits compression of elastic particles is ?

A. anthracite

B. sandstone

C. limestone

D. mudstone

Which of the following rock types is formed through the ejection of magma onto the surface of the earth?

A. Lignite

B. Granite

C. Slate

D. Basalt

Rocks that are composed of particles derived previously existing rocks are referred to as?

A. Metamorphic rocks

B. intrusive igneous rocks

C. sedimentary rocks

D. extrusive igneous rocks

An ox-bow lake is usually located in a?

A. volcanic crater

B. karst valley

C. river valley

D. desert oasis

The phenomenon of change in direction of wave fronts as the approach the sea shore is known as a?

A. wave refraction

B. tidal wave movement

C. wave drifting

D. retrogradation

The storm which occurs over the China Sea between latitudes 8^θ and 15^θ N and S of the equator is a?

A. tropical thunderstorm

B. torando

C. typhoon

D. temperature thunderstorm