Problem: Energy gives rise to weight when it is trapped in a system with zero momentum, where it can be weighed. It is also equivalent to mass, and this mass is always associated with it. Mass is also equivalent to a certain amount of energy, and likewise always appears associated with it, as described in mass-energy equivalence. The formula E = mc, derived by Albert Einstein (1905) quantifies the relationship between rest-mass and rest-energy within the concept of special relativity. In different theoretical frameworks, similar formulas were derived by J. J. Thomson (1881), Henri Poincare (1900), Friedrich Hasenohrl (1904) and others (see Mass-energy equivalence#History for further information).
In what year did Weinstein create E = mc2?
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Answer: unanswerable

Problem: METRO began light rail service on January 1, 2004, with the inaugural track ("Red Line") running about 8 miles (13 km) from the University of HoustonDowntown (UHD), which traverses through the Texas Medical Center and terminates at NRG Park. METRO is currently in the design phase of a 10-year expansion plan that will add five more lines. and expand the current Red Line. Amtrak, the national passenger rail system, provides service three times a week to Houston via the Sunset Limited (Los AngelesNew Orleans), which stops at a train station on the north side of the downtown area. The station saw 14,891 boardings and alightings in fiscal year 2008. In 2012, there was a 25 percent increase in ridership to 20,327 passengers embarking from the Houston Amtrak station.
How wide was the first light rail line in Houston?
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Answer: unanswerable

Problem: Dannatt criticised a remnant "Cold War mentality", with military expenditures based on retaining a capability against a direct conventional strategic threat; He said currently only 10% of the MoD's equipment programme budget between 2003 and 2018 was to be invested in the "land environment"at a time when Britain was engaged in land-based wars in Afghanistan and Iraq.
What is it called when Iraq was criticized for their military budget to stop a threat?
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Answer:
unanswerable