Passage: A standard-gauge railway is a railway with a track gauge of 1,435 mm (4 ft 8 in). The standard gauge is also called Stephenson gauge after George Stephenson, International gauge, UIC gauge, uniform gauge, normal gauge and European gauge in the EU and Russia. It is the most widely used railway track gauge across the world with approximately 55 % of the lines in the world using it. All high-speed rail lines, except those in Russia, Finland, Portugal and Uzbekistan, use standard gauge. The distance between the inside edges of the rails is defined to be 1435 mm except in the United States, where it is still defined in Imperial and US customary units as approximately 4 ft 8 in.

Question: Based on this passage, what is the standard width of train tracks? Let's do a good job answering this.
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Stream of consciousness: To answer the above question, the relevant sentence is: A standard-gauge railway is a railway with a track gauge of 1,435 mm (4 ft 8 in).... The answer is 1,435 mm ( 4 ft 8 in ).

Context: The Biopac Student Lab is a proprietary teaching device and method introduced in 1995 as a digital replacement for aging chart recorders and oscilloscopes that were widely used in undergraduate teaching laboratories prior to that time. It is manufactured by BIOPAC Systems, Inc., of Goleta, California. The advent of low cost personal computers meant that older analog technologies could be replaced with powerful and less expensive computerized alternatives.

Question: what is biopac and what does it do? Let's do a good job answering this.
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Stream of consciousness: The relevant information to answer the above question is: The Biopac Student Lab is a proprietary teaching device and method introduced in 1995 as a digital replacement for aging chart recorders and oscilloscopes that were widely used in undergraduate teaching laboratories prior to that time.... The answer is a proprietary teaching device and method introduced in 1995 as a digital replacement for aging chart recorders and oscilloscopes that were widely used in undergraduate teaching laboratories prior to that time.

The song is also sung at association football clubs around the world, where it is performed by a massed chorus of supporters on matchday; this tradition began at Liverpool F.C. after the chart success of the 1963 single of the song by the local Liverpool group Gerry and the Pacemakers.

When did liverpool start using you'll never walk alone? Let's do a good job answering this.
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Stream of consciousness: To answer this question, we should know that: The song is also sung at association football clubs around the world, where it is performed by a massed chorus of supporters on matchday; this tradition began at Liverpool F.C. after the chart success of the 1963 single of the song by the local Liverpool group Gerry and the Pacemakers.... The answer is after the chart success of the 1963 single of the song by the local Liverpool group Gerry and the Pacemakers.