Extract the answer to the question from the following context. Question: what is the second time period mentioned? Context: In 1931, RCA Victor introduced their vinyl-based Victrolac compound as a material for some unusual-format and special-purpose records. By the end of the 1930s vinyl's advantages of light weight, relative unbreakability and low surface noise had made it the material of choice for prerecorded radio programming and other critical applications. When it came to ordinary 78 rpm records, however, the much higher cost of the raw material, as well as its vulnerability to the heavy pickups and crudely mass-produced steel needles still commonly used in home record players, made its general substitution for shellac impractical at that time. During the Second World War, the United States Armed Forces produced thousands of 12-inch vinyl 78 rpm V-Discs for use by the troops overseas. After the war, the wider use of vinyl became more practical as new record players with relatively lightweight crystal pickups and precision-ground styli made of sapphire or an exotic osmium alloy proliferated. In late 1945, RCA Victor began offering special transparent red vinyl De Luxe pressings of some classical 78s, at a de luxe price. Later, Decca Records introduced vinyl Deccalite 78s, while other record companies came up with vinyl concoctions such as Metrolite, Merco Plastic and Sav-o-flex, but these were mainly used to produce "unbreakable" children's records and special thin vinyl DJ pressings for shipment to radio stations.
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Answer: end of the 1930s

Extract the answer to the question from the following context. Question: The fact that in the tongue of people from the Netherlands often utilizes parcels of speech that are made up of other parcels of speech meshed together results in the prodigious use of what element of language put to paper? Context: Dutch is written using the Latin script. Dutch uses one additional character beyond the standard alphabet, the digraph IJ. It has a relatively high proportion of doubled letters, both vowels and consonants, due to the formation of compound words and also to the spelling devices for distinguishing the many vowel sounds in the Dutch language. An example of five consecutive doubled letters is the word voorraaddoos (food storage container). The diaeresis (Dutch: trema) is used to mark vowels that are pronounced separately when involving a pre- or suffix. Whereas a hyphen is used when this problem occurs in compound words. For example; "beinvloed" (influenced), but zee-eend (sea duck). Generally, other diacritical marks only occur in loanwords, though the acute accent can also be used for emphasis or to differentiate between two forms. Its most common use is to differentiate between the indefinite article 'een' (a, an) and the numeral 'een' (one).
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Answer: relatively high proportion of doubled letters

Extract the answer to the question from the following context. Question: A commission investigating the existence of a protocol was led by? Context: For decades, it was the official policy of the Soviet Union to deny the existence of the secret protocol to the SovietGerman Pact. At the behest of Mikhail Gorbachev, Alexander Nikolaevich Yakovlev headed a commission investigating the existence of such a protocol. In December 1989, the commission concluded that the protocol had existed and revealed its findings to the Congress of People's Deputies of the Soviet Union. As a result, the Congress passed the declaration confirming the existence of the secret protocols, condemning and denouncing them. Both successor-states of the pact parties have declared the secret protocols to be invalid from the moment they were signed. The Federal Republic of Germany declared this on September 1, 1989 and the Soviet Union on December 24, 1989, following an examination of the microfilmed copy of the German originals.
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Answer:
Alexander Nikolaevich Yakovlev