61. In which year, Chilarai managed to occupy the capital of Ahom, Garhgaon

(A) 1558
(B) 1561
(C) 1562
(D) 1563

62. The average gradient of the Brahmaputra plain is

(A) 14 cm per km
(B) 16 cm per km
(C) 17 cm per km
(D) 19 cm per km

63. The total length of the Brahmaputra river is

(A) 2856 km
(B) 2892 km
(C) 2900 Km
(D) 2953 km

64. The total length of the Brahmaputra river in India is

(A) 916 km
(B) 925 km
(C) 936 Km
(D) 968 km

65. When Petroleum was first discovered in Assam

(A) 1885
(B) 1889
(C) 1896
(D) 1901