In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

Q: The most heat-treatable alloys are decided but only?, Context: Conversely, most heat-treatable alloys are precipitation hardening alloys, which produce the opposite effects that steel does. When heated to form a solution and then cooled quickly, these alloys become much softer than normal, during the diffusionless transformation, and then harden as they age. The solutes in these alloys will precipitate over time, forming intermetallic phases, which are difficult to discern from the base metal. Unlike steel, in which the solid solution separates to form different crystal phases, precipitation hardening alloys separate to form different phases within the same crystal. These intermetallic alloys appear homogeneous in crystal structure, but tend to behave heterogeneous, becoming hard and somewhat brittle.

A: Conversely
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Q: What did his thinking conflict with?, Context: In the early 11th century, the Muslim physicist Ibn al-Haytham (Alhacen or Alhazen) discussed space perception and its epistemological implications in his Book of Optics (1021), he also rejected Aristotle's definition of topos (Physics IV) by way of geometric demonstrations and defined place as a mathematical spatial extension. His experimental proof of the intromission model of vision led to changes in the understanding of the visual perception of space, contrary to the previous emission theory of vision supported by Euclid and Ptolemy. In "tying the visual perception of space to prior bodily experience, Alhacen unequivocally rejected the intuitiveness of spatial perception and, therefore, the autonomy of vision. Without tangible notions of distance and size for correlation, sight can tell us next to nothing about such things."

A: Aristotle's definition of topos
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Q: what is derived from the grass radical over two 十?, Context: The use of such contractions is as old as Chinese characters themselves, and they have frequently been found in religious or ritual use. In the Oracle Bone script, personal names, ritual items, and even phrases such as 受又(祐) shòu yòu "receive blessings" are commonly contracted into single characters. A dramatic example is that in medieval manuscripts 菩薩 púsà "bodhisattva" (simplified: 菩萨) is sometimes written with a single character formed of a 2×2 grid of four 十 (derived from the grass radical over two 十). However, for the sake of consistency and standardization, the CPC seeks to limit the use of such polysyllabic characters in public writing to ensure that every character only has one syllable.

A:
four 十
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