Problem: Please answer a question about the following article about Orthodox Judaism:
Haredi Judaism advocates segregation from non-Jewish culture, although not from non-Jewish society entirely. It is characterised by its focus on community-wide Torah study. Haredi Orthodoxy's differences with Modern Orthodoxy usually lie in interpretation of the nature of traditional halakhic concepts and in acceptable application of these concepts. Thus, engaging in the commercial world is a legitimate means to achieving a livelihood, but individuals should participate in modern society as little as possible. The same outlook is applied with regard to obtaining degrees necessary to enter one's intended profession: where tolerated in the Haredi society, attending secular institutions of higher education is viewed as a necessary but inferior activity. Academic interest is instead to be directed toward the religious education found in the yeshiva. Both boys and girls attend school and may proceed to higher Torah study, starting anywhere between the ages of 13 and 18. A significant proportion of students, especially boys, remain in yeshiva until marriage (which is often arranged through facilitated dating – see shiduch), and many study in a kollel (Torah study institute for married men) for many years after marriage. Most Orthodox men (including many Modern Orthodox), even those not in Kollel, will study Torah daily.
What is a Torah study institute for married men called?
A: kollel
Problem: Please answer a question about the following article about Alloy:
The term alloy is used to describe a mixture of atoms in which the primary constituent is a metal. The primary metal is called the base, the matrix, or the solvent. The secondary constituents are often called solutes. If there is a mixture of only two types of atoms, not counting impurities, such as a copper-nickel alloy, then it is called a binary alloy. If there are three types of atoms forming the mixture, such as iron, nickel and chromium, then it is called a ternary alloy. An alloy with four constituents is a quaternary alloy, while a five-part alloy is termed a quinary alloy. Because the percentage of each constituent can be varied, with any mixture the entire range of possible variations is called a system. In this respect, all of the various forms of an alloy containing only two constituents, like iron and carbon, is called a binary system, while all of the alloy combinations possible with a ternary alloy, such as alloys of iron, carbon and chromium, is called a ternary system.
The matrix and the solvent are other names for what?
A: The primary metal
Problem: Please answer a question about the following article about On the Origin of Species:
Modern evolutionary theory continues to develop. Darwin's theory of evolution by natural selection, with its tree-like model of branching common descent, has become the unifying theory of the life sciences. The theory explains the diversity of living organisms and their adaptation to the environment. It makes sense of the geologic record, biogeography, parallels in embryonic development, biological homologies, vestigiality, cladistics, phylogenetics and other fields, with unrivalled explanatory power; it has also become essential to applied sciences such as medicine and agriculture. Despite the scientific consensus, a religion-based political controversy has developed over how evolution is taught in schools, especially in the United States.
What branching common descent theory has become the most unifying one of the life sciences?
A: Darwin's theory of evolution
Problem: Please answer a question about the following article about Lighting:
Measurement of light or photometry is generally concerned with the amount of useful light falling on a surface and the amount of light emerging from a lamp or other source, along with the colors that can be rendered by this light. The human eye responds differently to light from different parts of the visible spectrum, therefore photometric measurements must take the luminosity function into account when measuring the amount of useful light. The basic SI unit of measurement is the candela (cd), which describes the luminous intensity, all other photometric units are derived from the candela. Luminance for instance is a measure of the density of luminous intensity in a given direction. It describes the amount of light that passes through or is emitted from a particular area, and falls within a given solid angle. The SI unit for luminance is candela per square metre (cd/m2). The CGS unit of luminance is the stilb, which is equal to one candela per square centimetre or 10 kcd/m2. The amount of useful light emitted from a source or the luminous flux is measured in lumen (lm).
What is the amount of useful light emitted from a luminous flux measured in? 
A:
lumen (lm)