Hydrosphere refers to the combined mass of water :

1. in the oceans
2. rivers, streams and lakes
3. in the atmosphere
4. All of the above.

Ocean : 97% :: Fresh water : ……………

1. 3%
2. 2.3%
3. 0.7%
4. 0.66%

Name the oscillatory movements in water, manifested by an alternate rise and fall of the sea surface.

1. Tides
2. Waves
3. Spheres
4. Oscillations

Apogee : Earth-moon distance …………… :: Perigee : Earth-moon distance ……………

1. maximum, minimum
2. minimum, maximum
3. equal, equal
4. All of the above.