76. The radiation belts are zones in space around the
A. Earth
B. Jupiter and Saturn
C. Mercury
D. Earth, Jupiter and Saturn
77. The periods of different eras are further divided into
A. Eons
B. Epochs
C. Stages
D. Any of the above
78. The Plio-Pleistocene boundary lies about ____ years ago, at the beginning of the interval of warming after the last Pleistocene glaciations.
A. 1,00,000
B. 1,000
C. 10,000
D. 100
79. The production of wheat has increased mainly due to
A. Increase in area under wheat
B. Increase in yield per hectare
C. Increase in demand for wheat
D. Increase in prices