Questions

The solubility of a gas in a liquid is directly and inversely proportional to pressure and temperature respectively.

Acceleration is nothing but the rate at which velocity changes over time.

The EPA stands for Environment Protection Agency in U.S which studies pollution and other environmental health hazards.

Crop Rotation is the practice of growing a series of dissimilar or different types of crops in the same area in sequenced seasons. It is done so that the soil of farms is not used for only one set of nutrients. It helps in reducing soil erosion and increases soil fertility and crop yield. The British agriculturist Charles Townshend (1674–1738) popularised this revolutionary technique in the 18th century.

The Early Middle Ages have often been called the Dark Ages, and to some extent  they were truly dark. The people led a miserable life. Education was very uncommon. The helplessness of the comman man the arbitary rule of the king and the barons and the absence of national unity-all these conditions were common in Europe. The term 'Middle Ages' does not cover a uniform period for all the countries of the world.For Europe and the Westren World , the 'Middle Ages' are generally considered to be the period between AD 500 and AD 1500.

United States and Russia have together almost 400 billion tones. Which represents nearly 50% of world's reserves of coal.