Questions

The carbon arc lamp was the first widely-used type of electric light and the first commercially successful form of electric lamp.

Here are the Carbon Arc Lamp Uses :

-Super bright light, capable of lighting a large length of street or a large factory interior.

-Was the ONLY electric light available to light large areas from 1800 - 1901.

-Was cheaper to light streets with the arc lamp than gas or oil lamps.

Abul Fazl placed Mughal kingship as the highest station in the hierarchy of objects receiving light emanating from God (farr-i izadi). Abul Fazl was inspired by a famous Iranian Sufi, Shihabuddin Suhrawardi who first developed this idea. According to this idea, there was a hierarchy in which the Divine Light was transmitted to the king who then became the source of spiritual guidance for his subjects.

Hospitality actually means, taking care of guests in the best possible way.

Organizing, providing services and looking care after guests is included in it.

It means friendly and generous treatment of guests. 

Hospitality industry includes all companies involved in providing services for guests. They provide more mental satisfaction than tangible objects.