51. The layer of the earth, immediately below the crust, is called
A. outer core
B. inner core
C. inner mantle
D. outer mantle
52. The highest mountains in Africa, which is not part of any mountains chain, is
A. Mt. Aconcagua
B. Mt. Kilimanjaro
C. Mt. Kosciuszko
D. Mont Blanc
53. The heavier silicates named as ‘Sima’ or silica + magnesium are most abundant in the
A. crust
B. core
C. mantle
D. ocean floors
54. The imaginary line on the earth’s surface, which closely follows the 180 º meridian, is called the
A. International Date Line
B. Tropic of Cancer
C. Equator
D. Prime Meridian
55. The largest part of our hydrosphere is
A. Atlantic Ocean
B. Indian Ocean
C. Pacific ocean
D. Antarctica ocean