This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.

Passage: Naturally occurring glass, especially the volcanic glass obsidian, has been used by many Stone Age societies across the globe for the production of sharp cutting tools and, due to its limited source areas, was extensively traded. But in general, archaeological evidence suggests that the first true glass was made in coastal north Syria, Mesopotamia or ancient Egypt. The earliest known glass objects, of the mid third millennium BCE, were beads, perhaps initially created as accidental by-products of metal-working (slags) or during the production of faience, a pre-glass vitreous material made by a process similar to glazing. Question: What was obsidian used to make in prehistoric times?
cutting tools

Passage: Rajasthan is known for its traditional, colorful art. The block prints, tie and dye prints, Bagaru prints, Sanganer prints, and Zari embroidery are major export products from Rajasthan. Handicraft items like wooden furniture and crafts, carpets, and blue pottery are commonly found here. Shopping reflects the colorful culture, Rajasthani clothes have a lot of mirror work and embroidery. A Rajasthani traditional dress for females comprises an ankle-length skirt and a short top, also known as a lehenga or a chaniya choli. A piece of cloth is used to cover the head, both for protection from heat and maintenance of modesty. Rajasthani dresses are usually designed in bright colors like blue, yellow and orange. Question: Females in Rajasthan wear what type of traditional clothing?
ankle-length skirt and a short top

Passage: Prior to 1917, Turkey used the lunar Islamic calendar with the Hegira era for general purposes and the Julian calendar for fiscal purposes. The start of the fiscal year was eventually fixed at 1 March and the year number was roughly equivalent to the Hegira year (see Rumi calendar). As the solar year is longer than the lunar year this originally entailed the use of "escape years" every so often when the number of the fiscal year would jump. From 1 March 1917 the fiscal year became Gregorian, rather than Julian. On 1 January 1926 the use of the Gregorian calendar was extended to include use for general purposes and the number of the year became the same as in other countries. Question: When did Turkey start using the Gregorian calendar for all purposes?

1 January 1926