QUES: In physics, the standard definition of a glass (or vitreous solid) is a solid formed by rapid melt quenching. The term glass is often used to describe any amorphous solid that exhibits a glass transition temperature Tg. If the cooling is sufficiently rapid (relative to the characteristic crystallization time) then crystallization is prevented and instead the disordered atomic configuration of the supercooled liquid is frozen into the solid state at Tg. The tendency for a material to form a glass while quenched is called glass-forming ability. This ability can be predicted by the rigidity theory. Generally, the structure of a glass exists in a metastable state with respect to its crystalline form, although in certain circumstances, for example in atactic polymers, there is no crystalline analogue of the amorphous phase.
What predicts glass-forming ability?

ANS: rigidity theory

QUES: On the next day, December 18, protests turned into civil unrest as clashes between troops, volunteers, militia units, and Kazakh students turned into a wide-scale confrontation. The clashes could only be controlled on the third day. The Almaty events were followed by smaller protests and demonstrations in Shymkent, Pavlodar, Karaganda, and Taldykorgan. Reports from Kazakh SSR authorities estimated that the riots drew 3,000 people. Other estimates are of at least 30,000 to 40,000 protestors with 5,000 arrested and jailed, and an unknown number of casualties. Jeltoqsan leaders say over 60,000 Kazakhs participated in the protests. According to the Kazakh SSR government, there were two deaths during the riots, including a volunteer police worker and a student. Both of them had died due to blows to the head. About 100 others were detained and several others were sentenced to terms in labor camps. Sources cited by the Library of Congress claimed that at least 200 people died or were summarily executed soon thereafter; some accounts estimate casualties at more than 1,000. The writer Mukhtar Shakhanov claimed that a KGB officer testified that 168 protesters were killed, but that figure remains unconfirmed.
Who was demonstrating?

ANS: Kazakh students

QUES: In August 1836, two real estate entrepreneurs—Augustus Chapman Allen and John Kirby Allen—from New York, purchased 6,642 acres (26.88 km2) of land along Buffalo Bayou with the intent of founding a city. The Allen brothers decided to name the city after Sam Houston, the popular general at the Battle of San Jacinto, who was elected President of Texas in September 1836. The great majority of slaves in Texas came with their owners from the older slave states. Sizable numbers, however, came through the domestic slave trade. New Orleans was the center of this trade in the Deep South, but there were slave dealers in Houston. Thousands of enslaved African-Americans lived near the city before the Civil War. Many of them near the city worked on sugar and cotton plantations, while most of those in the city limits had domestic and artisan jobs. In 1860 forty-nine percent of the city's population was enslaved. A few slaves, perhaps as many as 2,000 between 1835 and 1865, came through the illegal African trade. Post-war Texas grew rapidly as migrants poured into the cotton lands of the state. They also brought or purchased enslaved African Americans, whose numbers nearly tripled in the state from 1850 to 1860, from 58,000 to 182,566.
 What was the reason the Allen brothers sold land in 1836?

ANS: unanswerable

QUES: To make pulp from wood, a chemical pulping process separates lignin from cellulose fibres. This is accomplished by dissolving lignin in a cooking liquor, so that it may be washed from the cellulose; this preserves the length of the cellulose fibres. Paper made from chemical pulps are also known as wood-free papers–not to be confused with tree-free paper; this is because they do not contain lignin, which deteriorates over time. The pulp can also be bleached to produce white paper, but this consumes 5% of the fibres; chemical pulping processes are not used to make paper made from cotton, which is already 90% cellulose.
What is wood dissolved in to get clean from cellulose?

ANS:
unanswerable