2231: Seasons on the Earth are caused due to
(a) The elliptical orbit of the Earth
(b) Alteration/change in the speed of revolution of the Earth
(c) Inclination of the Earth on its axis of rotation
(d) Differences in the amount of energy received from the Sun
2232: Which one of the following planets has largest number of natural satellites or moons?
(a) Venus
(b) Mars
(c) Jupiter
(d) Saturn
2233: The first among the following to establish trade links with India were:
(a) Dutch
(b) French
(c) Portuguese
(d) English
2234: What is the approximate mean velocity with which the Earth moves round the Sun in its orbit ?
(a) 20 km/s
(b) 30 km/s
(c) 40 km/s
(d) 50 km/s
2235: Mixture of which one of the following pairs of gases is the cause of occurrence of most of the explosions in mines?
(a) Hydrogen and oxygen
(b) Oxygen and acetylene
(c) Methane and air
(d) Carbon dioxide and methane