Which of the following is a communicable disease?

• Measles
• Scurvy
• Asthma
• Diabetes
Solution
Correct Option: A  [ Measles ]

Explanation:

Which of the following contains maximum carbon dioxide ?

• Grasslands
• Forests
• Oceans
• Agroecosystems
Solution
Correct Option: C  [ Oceans ]

Explanation:

Solutions are of many types. Consider the following types of solution with an example each:

(i) Gas in liquid - Vinegar

(ii) Solid in liquid - Brine

(iii) Solid in solid - Brass

(iv) Liquid in liquid - Coca-Cola

Select the correctly matched pairs using the codes given below.

• (i) and (ii) only
• (ii) and (iii) only
• (i), (iii) and (iv) only
• (ii), (iii) and (iv) only
Solution
Correct Option: B  [ (ii) and (iii) only ]

Explanation:

How much time the light from Sun takes to reach the Earth ?

• 2 minutes
• 4 minutes
• 8 minutes
• 12 minutes
Solution
Correct Option: C  [ 8 minutes ]

Explanation: 8 minutes and 20 seconds

How much blood does a man have in his body?

• 4 %
• 10 %
• 7 %
• None of these
Solution
Correct Option: C  [ 7 % ]

Explanation:

Part of earth where life exist is known as:

• Lithosphere
• Hydrosphere
• Atmosphere
• Biosphere
Solution
Correct Option: D  [ Biosphere ]

Explanation:

Which of the following statements is correct ?

• Protons are negatively charged and are present in the nucleus
• Electrons are positively charged and are present in the nucleus
• Electrons are negatively charged and are present in the orbits
• The entire mass of atom is distributed in the orbits
Solution
Correct Option: C  [ Electrons are negatively charged and are present in the orbits ]

Explanation:

What does the term Dolby B or Dolby C printed on tape recorders and other sound systems refer to?

• frequency modulated system
• amplitude modulated system
• noise reduction circuit
• both DC and AC power can be used
Solution
Correct Option: C  [ noise reduction circuit ]

Explanation:

Which of the following is the best conductor of heat ?

• mercury
• silver
• leather
• benzene
Solution
Correct Option: B  [ silver ]

Explanation:

Brass gets discoloured in air due to constant exposure in presence of:

• Aluminium sulphide
• Aluminium phosphide
• Hydrogen sulphide
• Hydrogenated wafers
Solution
Correct Option: C  [ Hydrogen sulphide ]

Explanation: