Which of the following statement is true?

• A primary key is also a candidate key

• Each relation has at least one foreign key

• Foreign keys can't have null values

• Foreign keys can't have null values

Tsunami is the name given to which of the following?

• Earthquake

• Cyclone

• Tidal Waves

• Tidal Waves

The first Indian citizen to get commercial Pilot's Licence was

• Vijaypat Singhania

• J.R.D. Tata

• Captain Gopinath

• Captain Gopinath

The least preferred technique in the disposal of Municipal Solid Waste is

• Incineration

• Composting

• Land filling

• Land filling

A bomb explodes on the moon. You will hear its sound on earth after ........

• 20 min

• 2 hours 20 min

• 3.7 hours

• 3.7 hours

Which of the following is/are 'rain cloud'?
1.  Cirrus                               2.  Nimbostratus
3.  Cumulonimbus                  4.  Altocumulus

• 1 and 2

• 2 and 3

• 3 and 4

• 3 and 4

Which of the following is used as non-stick coating for cooking utensils?

• Perspex

• Styrofoam

• Polystyrene

• Polystyrene

Which one of the following takes place during a nuclear fusion?

• A heavy nucleus bombarded by neutrons breaks up

• A heavy nucleus breaks up spontaneously

• Two light nuclei combine to form a heavy nucleus

• Two light nuclei combine to form a heavy nucleus

According to the Indian Constitution, who has the power to declare emergency?

• Prime Minister

• President

• Chief Justice

• Chief Justice

Particulates ( 1μ mg ) remaining suspended in air indefinitely and transported by wind currents are called

• Mists

• Fumes

• Aerosols

• Smoke