Problem: IBM:

In 2012, Fortune ranked IBM the second largest U.S. firm in terms of number of employees (435,000 worldwide), the fourth largest in terms of market capitalization, the ninth most profitable, and the nineteenth largest firm in terms of revenue. Globally, the company was ranked the 31st largest in terms of revenue by Forbes for 2011. Other rankings for 2011/2012 include №1 company for leaders (Fortune), №1 green company in the United States (Newsweek), №2 best global brand (Interbrand), №2 most respected company (Barron's), №5 most admired company (Fortune), and №18 most innovative company (Fast Company).

How was Forbes ranked globally for revenue in 2011?
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A: unanswerable


Problem: Vacuum:

The SI unit of pressure is the pascal (symbol Pa), but vacuum is often measured in torrs, named for Torricelli, an early Italian physicist (1608–1647). A torr is equal to the displacement of a millimeter of mercury (mmHg) in a manometer with 1 torr equaling 133.3223684 pascals above absolute zero pressure. Vacuum is often also measured on the barometric scale or as a percentage of atmospheric pressure in bars or atmospheres. Low vacuum is often measured in millimeters of mercury (mmHg) or pascals (Pa) below standard atmospheric pressure. "Below atmospheric" means that the absolute pressure is equal to the current atmospheric pressure.

During what years was mercury commonly in use?
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A: unanswerable


Problem: A cappella:

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 promote in 20 BCE?
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A: unanswerable


Problem: Sichuan:

The Yangtze River and its tributaries flows through the mountains of western Sichuan and the Sichuan Basin; thus, the province is upstream of the great cities that stand along the Yangtze River further to the east, such as Chongqing, Wuhan, Nanjing and Shanghai. One of the major tributaries of the Yangtze within the province is the Min River of central Sichuan, which joins the Yangtze at Yibin. Sichuan's 4 main rivers, as Sichuan means literally, are Jaling Jiang, Tuo Jiang, Yalong Jiang, and Jinsha Jiang.

What are the 4 main rivers in Sichuan?
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A:
Jaling Jiang, Tuo Jiang, Yalong Jiang, and Jinsha Jiang