Questions

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.

Iconic attraction of India Taj Mahal has emerged as the 5th most popular landmark in the world and 2nd in Asia, according to the online travel portal TripAdvisor’s ‘Travellers’ Choice Awards for Landmarks. Globally, Angkor Wat in Cambodia, Sheikh Zayed Grand Mosque Center in Abu Dhabi, Mezquita Cathedral de Cordoba in Spain, and St Peter’s Basilica in Italy, bagged the first four ranks respectively. Whereas, the top 10 landmarks in Asia has been topped by Angkor Wat, followed by Taj Mahal on the second place. Apart from this, Taj Mahal has also ranked first in the list of popular landmarks in India, followed by AmberFort, Jaipur; Swaminarayan Akshardham, New Delhi, etc.

In chemistry, a metal is an element that readily forms positive ions (cations) and has metallic bonds. Metals are opaque, lustrous elements that are good conductors of heat and electricity. Most metals are malleable and ductile and are, in general, denser than the other elemental substances.

Examples of metals are aluminium, copper, iron, tin, gold, lead, silver, titanium, uranium, and zinc.

Here Se - Selenium is an element but is not a metal, S - Sulphur is not a metal and I - Iodine is also not a metal.

Hence, Zn - Zinc is the only metal in the given options.

Scope, quality, and cost are the triple constraints. Quality is a function of these three areas and can impact them; however it is not considered one of the components of the triple constraint. Therefore, Answer A, B, and C are incorect.

Plantain plant is a herb, because it does not have an aerial stem - what appears as a stem is really the leaves with sheathing bases. As the piant lives for several years it is called perennial herb