Problem: Miami:

Miami's heavy-rail rapid transit system, Metrorail, is an elevated system comprising two lines and 23 stations on a 24.4-mile (39.3 km)-long line. Metrorail connects the urban western suburbs of Hialeah, Medley, and inner-city Miami with suburban The Roads, Coconut Grove, Coral Gables, South Miami and urban Kendall via the central business districts of Miami International Airport, the Civic Center, and Downtown. A free, elevated people mover, Metromover, operates 21 stations on three different lines in greater Downtown Miami, with a station at roughly every two blocks of Downtown and Brickell. Several expansion projects are being funded by a transit development sales tax surcharge throughout Miami-Dade County.

What is the name of Miami's heavy-rail system?
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A: Metrorail


Problem: Alps:

In the high villages people live in homes built according to medieval designs that withstand cold winters. The kitchen is separated from the living area (called the stube, the area of the home heated by a stove), and second-floor bedrooms benefit from rising heat. The typical Swiss chalet originated in the Bernese Oberland. Chalets often face south or downhill, and are built of solid wood, with a steeply gabled roof to allow accumulated snow to slide off easily. Stairs leading to upper levels are sometimes built on the outside, and balconies are sometimes enclosed.

What do people in high villages build their homes according to?
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A: medieval designs that withstand cold winters


Problem: Adolescence:

In females, changes in the primary sex characteristics involve growth of the uterus, vagina, and other aspects of the reproductive system. Menarche, the beginning of menstruation, is a relatively late development which follows a long series of hormonal changes. Generally, a girl is not fully fertile until several years after menarche, as regular ovulation follows menarche by about two years. Unlike males, therefore, females usually appear physically mature before they are capable of becoming pregnant.

How many years does regular ovulation follow menarche?
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A: two years


Problem: Energy:

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 = mc², 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 Poincaré (1900), Friedrich Hasenöhrl (1904) and others (see Mass-energy equivalence#History for further information).

Who created the formula E = mc2?
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A:
Albert Einstein