Short answers, pulled from the story.
The English word orange derives from the fruit's name, which travelled through Sanskrit nāraṅga, Persian nārang, Arabic, Italian arancia, and French pomme d'orange before entering English. The earliest recorded use of orange as a colour name in English is from 1502, in a description of clothing purchased for Margaret Tudor.
Orange light has a dominant wavelength between roughly 585 and 620 nanometres. In the HSV colour model it has a hue of 30 degrees, and in the RGB model it is produced by combining high-intensity red light with lower-intensity green light, with blue turned off entirely.
The House of Orange-Nassau originated in 1163 in the Principality of Orange, a feudal state of 108 square miles north of Avignon in southern France, which was named after the Celtic water god Arausio. The royal family formally adopted the colour orange in the 1570s, associating it with Protestantism through their role in the French Wars of Religion.
In Buddhism, saffron orange represents illumination and the highest state of perfection. The Buddhist texts specify that robe dye must come from six natural substances including roots, bark, leaves, and fruits, with saffron and ochre from the curcuma longa plant or jackfruit heartwood being the most common colours.
Carotenes, a type of photosynthetic pigment, give carrots, pumpkins, sweet potatoes, and many other fruits and vegetables their orange colour. Autumn leaves show the same pigment after the production of green chlorophyll stops when temperatures drop. The long orange Dutch carrot, first described in 1721, is the ancestor of the most common orange carrot varieties in supermarkets today.
Agent Orange took its name from the colour of the orange steel drums in which the herbicide was stored, not from the colour of the chemical itself. It was sprayed from aircraft by the Royal Air Force during the Malayan Emergency and by the US Air Force during the Vietnam War, and was later linked to birth defects and other health problems.