The lithosphere is the earth’s outer crust. The lithosphere is located below the atmosphere and above the asthenosphere.It is an irregular surface with various landforms such as mountains, plateaus, deserts, plains, valleys, etc. The upper layer of the lithosphere is covered with soil rich in nutrients. It, thereby supports the ... Read More

A heart beats about 100,000 times a day and pumps about 7,200 litres (1,900 gallons) of blood. An adult's body holds about five litres of blood.

Polyethylene terephthalate commonly abbreviated PET is the most common resin of the polyester family and is used in fibres for clothing, containers for liquids and foods, thermoforming for manufacturing, and in combination with glass fibre for engineering resins.1. It can be made into Fibre or Plastic.2. PET as plastic is ... Read More

Irrigation is the process of supplying the required amount of water to plants at needed intervals. It helps to grow agricultural crops, maintains landscapes, and also provides the barren land with a new vegetative cover during the periods of average or less rainfall. There are different types of irrigation ... Read More

Cambium is the layer of actively dividing cells between the vascular tissues, xylem, and phloem. It helps in the secondary growth of stems and roots.

There are three types of fibres found in connective tissue- collagen, elastic and reticular.1) Collagen fibres are secreted in the form of tropocollagen molecules by the fibroblasts and then they assemble extracellularly to form striated collagen fibrils. 2) Elastic fibres are composed of the protein elastin and differ from collagenous ... Read More

Black gold is a term used for oil or petroleum. It is because petroleum is black in color when it comes out of the ground. Prior to the discovery of petroleum, animal fat or whale blubber was used as a fuel. However, with the discovery of petroleum in Pennsylvania ... Read More

The symbol of the element Helium is He.Extra information: Helium is a chemical element with atomic number 2. It is a colourless, odourless, tasteless, non-toxic, inert, monatomic gas. It lies first in the noble gas group in the periodic table. Its boiling point is the lowest among all the elements.A ... Read More

Solution :Let a and b be any two real numbers. Consider the number x defined by$x = ab + (-a)(b) + (-a)(-b)$.We can write$x = ab + (-a)[ (b) + (-b) ]$        $= ab + (-a)(0)$  $= ab + 0$  $= ab$.Also, $x = [ a + (-a) ... Read More

Sericulture, also called silk farming, is the cultivation of silkworms to produce silk fibres. Silk fibers are combined into silk thread. The thread can then be twisted into silk yarn or woven into silk cloth.