Which of the following is the study of micro- organisms, mostly viruses and single called organisms such as bacteria, yeasts and protozoa ?

What causes the Moon’s phases?

A. The Sun lights up only one half of the Moon and as the Moon orbits the Earth we can sometimes see the unlit side of the Moon.
B. The Sun lights up only one half of the Moon and as the Sun orbits the Earth we can sometimes see the unlit side of the Moon.
C. The Earth’s shadow falls on the Moon, blocking the sunlight.
D. The Moon’s shadow falls on the Earth, blocking the sunlight.

A. Ozone
B. Radium
C. Cholorine
D. Neutron

A. watt
B. Pascal
C. Candela
D. Joule

Glass is made of the mixture of______________?

A. Quartz and Mica
B. Sand and Salt
C. Sand and Silicates
D. None of these

The blue colour of clear sky is due to_______________?

A. Reflection of light
B. Refraction of light
C. Diffraction of light
D. Dispersion of light