This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
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Question: The emergence of Susa as a city, as determined by radiocarbon dating, dates back to early 4,395 BC. There are dozens of prehistoric sites across the Iranian plateau, pointing to the existence of ancient cultures and urban settlements in the 4th millennium BC. During the Bronze Age, Iran was home to several civilizations including Elam, Jiroft, and Zayande River. Elam, the most prominent of these civilizations, developed in the southwest of Iran, alongside those in Mesopotamia. The emergence of writing in Elam was paralleled to Sumer, and the Elamite cuneiform was developed since the 3rd millennium BC.

Answer: What ancient city dates back as early as 4395 BC in Iran?


Question: The geographical regions in which Iranian languages were spoken were pushed back in several areas by newly neighbouring languages. Arabic spread into some parts of Western Iran (Khuzestan), and Turkic languages spread through much of Central Asia, displacing various Iranian languages such as Sogdian and Bactrian in parts of what is today Turkmenistan, Uzbekistan and Tajikistan. In Eastern Europe, mostly comprising the territory of modern-day Ukraine, southern European Russia, and parts of the Balkans, the core region of the native Scythians, Sarmatians, and Alans had been decisively been taken over as a result of absorption and assimilation (e.g. Slavicisation) by the various Proto-Slavic population of the region, by the 6th century AD. This resulted in the displacement and extinction of the once predominant Scythian languages of the region. Sogdian's close relative Yaghnobi barely survives in a small area of the Zarafshan valley east of Samarkand, and Saka as Ossetic in the Caucasus, which is the sole remnant of the once predominant Scythian languages in Eastern Europe proper and large parts of the North Caucasus. Various small Iranian languages in the Pamirs survive that are derived from Eastern Iranian.

Answer: What is another term for Western Iran?


Question: In quantum mechanics, energy is defined in terms of the energy operator as a time derivative of the wave function. The Schrödinger equation equates the energy operator to the full energy of a particle or a system. Its results can be considered as a definition of measurement of energy in quantum mechanics. The Schrödinger equation describes the space- and time-dependence of a slowly changing (non-relativistic) wave function of quantum systems. The solution of this equation for a bound system is discrete (a set of permitted states, each characterized by an energy level) which results in the concept of quanta. In the solution of the Schrödinger equation for any oscillator (vibrator) and for electromagnetic waves in a vacuum, the resulting energy states are related to the frequency by Planck's relation:  (where  is Planck's constant and  the frequency). In the case of an electromagnetic wave these energy states are called quanta of light or photons.

Answer:
In quantum mechanics, what is defined in terms of the energy operator as a time derivative of the wave function?