Problem: Please answer a question about the following article about Glacier:
Glaciers are broken into zones based on surface snowpack and melt conditions. The ablation zone is the region where there is a net loss in glacier mass. The equilibrium line separates the ablation zone and the accumulation zone; it is the altitude where the amount of new snow gained by accumulation is equal to the amount of ice lost through ablation. The upper part of a glacier, where accumulation exceeds ablation, is called the accumulation zone. In general, the accumulation zone accounts for 6070% of the glacier's surface area, more if the glacier calves icebergs. Ice in the accumulation zone is deep enough to exert a downward force that erodes underlying rock. After a glacier melts, it often leaves behind a bowl- or amphitheater-shaped depression that ranges in size from large basins like the Great Lakes to smaller mountain depressions known as cirques.
How much glacial surface area is typically considered accumulation zone?
A: 6070%

Question: Read this and answer the question

Matrix groups consist of matrices together with matrix multiplication. The general linear group GL(n, R) consists of all invertible n-by-n matrices with real entries. Its subgroups are referred to as matrix groups or linear groups. The dihedral group example mentioned above can be viewed as a (very small) matrix group. Another important matrix group is the special orthogonal group SO(n). It describes all possible rotations in n dimensions. Via Euler angles, rotation matrices are used in computer graphics.

What includes all invertible n-by-n matrices with real entries?
Answer: The general linear group

Problem: Being identified as either "black" or "white" in Australia during the 19th and early 20th centuries was critical in one's employment and social prospects. Various state-based Aboriginal Protection Boards were established which had virtually complete control over the lives of Indigenous Australians where they lived, their employment, marriage, education and included the power to separate children from their parents. Aborigines were not allowed to vote and were often confined to reserves and forced into low paid or effectively slave labour. The social position of mixed-race or "half-caste" individuals varied over time. A 1913 report by Sir Baldwin Spencer states that:
What year was his report from?
The answer is the following: 1913

Ahmad ibn Fadlan, an Arab traveler during the 10th century, provided one of the earliest written descriptions of the Rus': "They are as tall as a date palm, blond and ruddy, so that they do not need to wear a tunic nor a cloak; rather the men among them wear garments that only cover half of his body and leaves one of his hands free." Liutprand of Cremona, who was twice an envoy to the Byzantine court (949 and 968), identifies the "Russi" with the Norse ("the Russi, whom we call Norsemen by another name") but explains the name as a Greek term referring to their physical traits ("A certain people made up of a part of the Norse, whom the Greeks call [...] the Russi on account of their physical features, we designate as Norsemen because of the location of their origin."). Leo the Deacon, a 10th-century Byzantine historian and chronicler, refers to the Rus' as "Scythians" and notes that they tended to adopt Greek rituals and customs.
Which early traveler provided an early description of the Rus?
Ahmad ibn Fadlan

Input: Alfred North Whitehead
To put it another way, a thing or person is often seen as having a "defining essence" or a "core identity" that is unchanging, and describes what the thing or person really is. In this way of thinking, things and people are seen as fundamentally the same through time, with any changes being qualitative and secondary to their core identity (e.g. "Mark's hair has turned gray as he has gotten older, but he is still the same person"). But in Whitehead's cosmology, the only fundamentally existent things are discrete "occasions of experience" that overlap one another in time and space, and jointly make up the enduring person or thing. On the other hand, what ordinary thinking often regards as "the essence of a thing" or "the identity/core of a person" is an abstract generalization of what is regarded as that person or thing's most important or salient features across time. Identities do not define people, people define identities. Everything changes from moment to moment, and to think of anything as having an "enduring essence" misses the fact that "all things flow", though it is often a useful way of speaking.

In that line of thinking, how are changes described?
Output: qualitative and secondary to their core identity

Problem: Please answer a question about the following article about Computer:
Purely electronic circuit elements soon replaced their mechanical and electromechanical equivalents, at the same time that digital calculation replaced analog. The engineer Tommy Flowers, working at the Post Office Research Station in London in the 1930s, began to explore the possible use of electronics for the telephone exchange. Experimental equipment that he built in 1934 went into operation 5 years later, converting a portion of the telephone exchange network into an electronic data processing system, using thousands of vacuum tubes. In the US, John Vincent Atanasoff and Clifford E. Berry of Iowa State University developed and tested the AtanasoffBerry Computer (ABC) in 1942, the first "automatic electronic digital computer". This design was also all-electronic and used about 300 vacuum tubes, with capacitors fixed in a mechanically rotating drum for memory.
How many vacuum tubes did the Atanasoff-Berry computer use?
A:
about 300