Complementary angles are those whose sum is 90.

Given here, is a right angled triangle, where anfle C is 90 deg. In this, sum of Angles A + C = 90, since, sum of angles in a right angled triangle = 180, angle C = 90 and

hence sum of A + B = 180 - C = 180 - 90 = 90.

Hence, the pair of cimplementary angles in the given triangle = Angle A + B.

Thermal energy is caused by the motion of atoms and molecules in the matter.

1. Thermal energy is an example of kinetic energy, as it is due to the motion of particles, with motion being the key.
2. Thermal energy results in an object or a system having a temperature that can be measured.
3. Thermal energy can be transferred from one object or system to another in the form of heat.

About 71% of the earth's surface is covered with water. In that 71% only 4% of water is a fresh water.

The alphabet 'B' resembles same as a fly 'Bee' in pronouncing.

Market regulation system was introduced by Ala-ud-Din Khilji. He was the second and the most powerful ruler of the Khalji dynasty that ruled the Delhi Sultanate in the Indian subcontinent. 

A credit may signify a decrease in an asset account or an increase in a liability or capital stock account. 

A debit may signify an increase in an asset account.

Free floating anxiety is also known as Generalised Anxiety Disorder in which the individual may be unable to identify specific triggers for the anxiety.