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Alpine crystals have been studied and collected for hundreds of years, and began to be classified in the 18th century. Leonhard Euler studied the shapes of crystals, and by the 19th century crystal hunting was common in Alpine regions. David Friedrich Wiser amassed a collection of 8000 crystals that he studied and documented. In the 20th century Robert Parker wrote a well-known work about the rock crystals of the Swiss Alps; at the same period a commission was established to control and standardize the naming of Alpine minerals.
Who amassed a collection 8000 crystals?
A: David Friedrich Wiser

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Some symbiotic relationships are obligate, meaning that both symbionts entirely depend on each other for survival. For example, many lichens consist of fungal and photosynthetic symbionts that cannot live on their own. Others are facultative (optional): they can, but do not have to live with the other organism.
What is the type of symbiotic relationship where two organisms can't survive without each other?
A: obligate

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The Color Orange democracy group, led by Danish sculptor Jens Galschiøt, originally planned to join the Hong Kong Alliance relay and paint the "Pillar of Shame", a structure he built in Hong Kong to commemorate the 1989 Tiananmen Square protests. However, Galschiøt and two other people were denied entry to Hong Kong on April 26, 2008 due to "immigration reasons" and were forced to leave Hong Kong. In response, Lee Cheuk Yan, vice chairman of the Hong Kong Alliance in Support of Patriotic Democratic Movements in China, said, "It's outrageous that the government is willing to sacrifice the image of Hong Kong because of the torch relay." Hollywood actress Mia Farrow was also briefly questioned at the Hong Kong airport though officials allowed her to enter. She later gave a speech criticizing China's relations with Sudan in Hong Kong, as there was also a small minority of people protesting about China's role in the crisis of Darfur. Legislator Cheung Man Kwong have also said the government's decision allowing Farrow to enter while denying others is a double standard and a violation to Hong Kong's one country, two systems policy.
Which actress from America was initially held and then gave a speech about China and Sudan?
A: Mia Farrow

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The popularization of the Jewish chant may be found in the writings of the Jewish philosopher Philo, born 20 BCE. Weaving together Jewish and Greek thought, Philo promoted praise without instruments, and taught that "silent singing" (without even vocal chords) was better still. This view parted with the Jewish scriptures, where Israel offered praise with instruments by God's own command (2 Chronicles 29:25). The shofar is the only temple instrument still being used today in the synagogue, and it is only used from Rosh Chodesh Elul through the end of Yom Kippur. The shofar is used by itself, without any vocal accompaniment, and is limited to a very strictly defined set of sounds and specific places in the synagogue service.
What did Philo's views on the absence of instruments clash with?
A:
Jewish scriptures