instruction:
This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.
question:
Passage: Chopin has figured extensively in Polish literature, both in serious critical studies of his life and music and in fictional treatments. The earliest manifestation was probably an 1830 sonnet on Chopin by Leon Ulrich. French writers on Chopin (apart from Sand) have included Marcel Proust and André Gide; and he has also featured in works of Gottfried Benn and Boris Pasternak. There are numerous biographies of Chopin in English (see bibliography for some of these). Question: An 1830 sonnet was written about Chopin by what man?
answer:
Leon Ulrich


question:
Passage: First recognized in 1900 by Max Planck, it was originally the proportionality constant between the minimal increment of energy, E, of a hypothetical electrically charged oscillator in a cavity that contained black body radiation, and the frequency, f, of its associated electromagnetic wave. In 1905 the value E, the minimal energy increment of a hypothetical oscillator, was theoretically associated by Einstein with a "quantum" or minimal element of the energy of the electromagnetic wave itself. The light quantum behaved in some respects as an electrically neutral particle, as opposed to an electromagnetic wave. It was eventually called the photon. Question: Who discovered an association between the value E and quantum energy?
answer:
Einstein


question:
Passage: The CD was planned to be the successor of the gramophone record for playing music, rather than primarily as a data storage medium. From its origins as a musical format, CDs have grown to encompass other applications. In 1983, following the CD's introduction, Immink and Braat presented the first experiments with erasable compact discs during the 73rd AES Convention. In June 1985, the computer-readable CD-ROM (read-only memory) and, in 1990, CD-Recordable were introduced, also developed by both Sony and Philips. Recordable CDs were a new alternative to tape for recording music and copying music albums without defects introduced in compression used in other digital recording methods. Other newer video formats such as DVD and Blu-ray use the same physical geometry as CD, and most DVD and Blu-ray players are backward compatible with audio CD. Question: What year did Sony and Philips release CD-Recordable?
answer:

1990