There are 25 discs numbered 1 to 25. They are put in a closed box and shaken thoroughly. A disc is drawn at random from the box. Find the probability that the number on the disc is:

1. an odd number
2. divisible
...

The IUPAC name of dimethyl ether is

1. Ethoxy methane
2. Methoxy methane
3. Methoxy ethane                                                                                                                                                                     
4. Ethoxy ethane

Give two advantages of using bio-gas as a source of power.

₹7500 were divided equally among a certain number of children. Had there been 20 less children, each would have received ₹100 more. Find the original number of children.

Mention one way in which man is responsible for soil erosion.

Surgical method of sterilization in a woman involves cutting and tying of:

1. Ureter
2. Uterus
3. Urethra
4. Oviduct

Why is agriculture important in India?

An electromagnetic radiation is used for photography in fog.

1. Identify the radiation.
2. Why is this radiation mentioned by you, ideal for this purpose?

When does the nucleus of an atom tend to be radioactive

The diagram of an apparatus given below demonstrates a particular process in plants. Study the same and answer the questions that follow:

1. Name the apparatus.
2. Which phenomenon is demonstrated by this
...

The compound formed when haemoglobin combines with carbon dioxide in blood.

Lead nitrate solution is mixed with dilute hydrochloric acid and heated.

The 1914 and 1939 Wars that engulfed almost the entire world, were known as World Wars due to its unprecedented impact and damage. In this context, Mention any four terms of the Treaty of Versailles which...

What was the General Service Enlistment Act?

The wax-like layer on the epidermis of leaves which reduces transpiration.

Which property of sulphuric acid is shown by the reaction of concentrated sulphuric acid with:

1. Ethanol?
2. Carbon?