Questions

In music, a fugue is a contrapuntal compositional technique in two or more voices, built on a subject that is introduced at the beginning in imitation and which recurs frequently in the course of the composition. 

Hence, the main theme of a fugue is called the subject.

Molecular compounds are those with covalent bonds between the elements and those elements are typically non metals.

Here in the given options, Ar is an element. NaI has an ionic bond. Hence, N2O4 has a covalent bond between the two non metals and is a molecular compound.

A : B = (800 × 8+ 900+ 1000+ 1100+ 1200): (1600 × 8+ 1700+ 1800+ 1900+ 2000)
A : B = 53 : 101
Profit of A ⇒ 7700 ×53/154 = 2650 Rs.

silver is the best conductor of electricity.

When compared to remaining 3 metals, as Silver having more number of free electrons in its valency shell it is the good conductor of electricity.

Conductors Thermal Conductivity @ 25degree C

Silver --- 429
Copper --- 401
Gold --- 310
Aluminium --- 250

Indian Navy’s survey vessel INS Sarvekshak has become the India’s first warship to install solar power system on board. The solar power system works on sunlight and hence is 100% per cent reliable for power source that can be used for communication equipment, battery charging and general lightings onboard round the clock with battery outputs during night. The system is maintenance free.