Questions

SHORT is the required five letter word, which becomes SHORTER when two letters 'ER' are added to it.

Sound is a mechanical vibration and needs a medium for propagation. The higher the density of the medium, the faster the sound travels. So, sound cannot travel through vacuum.

As the sound travels faster in solids than liquids and gases, sound travels faster in the glass than Air and water.

A greenhouse gas is a gas in an atmosphere that absorbs and emits radiant energy within the thermal infrared range. This process is the fundamental cause of the greenhouse effect. 

Carbon dioxide is a main greenhouse gas, found in car exhaust pipes.
Methane and nitrous oxide is another type of greenhouse gas.

Oxygen is the only clean gas out there because we need it to survive. Therefore, the only gas that is not a greenhouse gas is Oxygen.

Gene flow means migration of genes from one to another. This gene flow is caused by individuals moving into population.

Steel is not a compound or element. Steel is an alloy of iron and carbon and other elements and hence it is a mixture. Because of its high tensile strength and low cost, it is a major component used in buildings, infrastructure, tools, ships, automobiles, machines, appliances, and weapons.

Bengaluru has became the second city in the country, and the first in south India, to have a full-fledged Metro rail in operation following the opening of a final 12-km section of the 42-km first phase of the Metro project. The first phase, comprising an 18-km east-west line and a 24-km north-south line, built at a cost of Rs 13,845 crore, was dedicated to the nation by President Pranab Mukherjee at an event in Bengaluru.