The collation of all known variants of a text is referred to as a variorum, namely a work of textual criticism whereby all variations and emendations are set side by side so that a reader can track how textual decisions have been made in the preparation of a text for publication. The Bible and the works of William Shakespeare have often been the subjects of variorum editions, although the same techniques have been applied with less frequency to many other works, such as Walt Whitman's Leaves of Grass, and the prose writings of Edward Fitzgerald.
Name two works that are often the subject of a variorum.
The Bible and the works of William Shakespeare


Input: Zinc
Zinc deficiency is crop plants' most common micronutrient deficiency; it is particularly common in high-pH soils. Zinc-deficient soil is cultivated in the cropland of about half of Turkey and India, a third of China, and most of Western Australia, and substantial responses to zinc fertilization have been reported in these areas. Plants that grow in soils that are zinc-deficient are more susceptible to disease. Zinc is primarily added to the soil through the weathering of rocks, but humans have added zinc through fossil fuel combustion, mine waste, phosphate fertilizers, pesticide (zinc phosphide), limestone, manure, sewage sludge, and particles from galvanized surfaces. Excess zinc is toxic to plants, although zinc toxicity is far less widespread.

In what type of soil is zinc deficiency most common?
Output: high-pH soils


Input: Article: Abnormal discoloration of wood often denotes a diseased condition, indicating unsoundness. The black check in western hemlock is the result of insect attacks. The reddish-brown streaks so common in hickory and certain other woods are mostly the result of injury by birds. The discoloration is merely an indication of an injury, and in all probability does not of itself affect the properties of the wood. Certain rot-producing fungi impart to wood characteristic colors which thus become symptomatic of weakness; however an attractive effect known as spalting produced by this process is often considered a desirable characteristic. Ordinary sap-staining is due to fungal growth, but does not necessarily produce a weakening effect.

Now answer this question: What animals cause the reddish-brown streaks of color in hickory wood?

Output: birds


Article: 
 Russia: On April 5 the Olympic torch arrived at Saint Petersburg, Russia. The length of the torch relay route in the city was 20 km, with the start at the Victory Square and finish at the Palace Square. Mixed martial arts icon and former PRIDE Heavyweight Champion Fedor Emelianenko was one the torch bearers. This gives him the distinction of the being the first active MMA fighter to carry the Olympic flame.

Question: Where in Russia was the first stop for the relay?
Ans: Saint Petersburg


Here is a question about this article: Ratification of the treaty the following year led to resumption of hostilities and in 1860, with Anglo-French forces marching on Beijing, the emperor and his court fled the capital for the imperial hunting lodge at Rehe. Once in Beijing, the Anglo-French forces looted the Old Summer Palace, and in an act of revenge for the arrest of several Englishmen, burnt it to the ground. Prince Gong, a younger half-brother of the emperor, who had been left as his brother's proxy in the capital, was forced to sign the Convention of Beijing. Meanwhile, the humiliated emperor died the following year at Rehe.
What is the answer to this question: What happened to the Old Summer Palace?
****
So... burnt it to the ground


Article: By 30 November, the PVA 13th Army Group managed to expel the U.S. Eighth Army from northwest Korea. Retreating from the north faster than they had counter-invaded, the Eighth Army crossed the 38th parallel border in mid December. UN morale hit rock bottom when commanding General Walton Walker of the U.S. Eighth Army was killed on 23 December 1950 in an automobile accident. In northeast Korea by 11 December, the U.S. X Corps managed to cripple the PVA 9th Army Group while establishing a defensive perimeter at the port city of Hungnam. The X Corps were forced to evacuate by 24 December in order to reinforce the badly depleted U.S. Eighth Army to the south.

Question: Whose death was not a direct casualty of the war?
Ans:
General Walton Walker