Which of the following is used in pencils?

• Graphite

• Sulphur

• Phosphorus

• Charcaol

Deficiency of which of the following causes non-clotting of blood?

Name the catalyst used in the conversion of milk into curd.

The blue revolution is related with 

The purpose of choke in a fluorescent lamp is

The apparent weight of a man in a lift is less than the real weight when

Addition of excessive amounts of heat to lake is referred to as

The mercury and sodium street lamps light up because of

From the national point of view which of the following indicates Micro Approach?

Competition for food, light and space is most severe in

The green colour seen in firework displays is due to the chloride salt of