Astronomers Have Discovered a Planet Orbiting Proxima Centauri, the Star

question 28

Multiple Choice

Astronomers have discovered a planet orbiting Proxima Centauri, the star closest to the Sun. This is a star of spectral type M, with 12% the mass of the Sun and 15% the size of the Sun. The habitable zone around this star would be

• A) much larger (wider) than the Sun's
• B) much closer to the star than the Sun's
• C) in about the same place as the Sun's asteroid belt
• D) much more narrow (small) than the diameter of any planet
• E) the source of all the UFO's that have been reported by UFO believers on Earth

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Definitions:

Marginal Cost

The elevation in costs incurred by the creation of an additional unit of a good or service.

Long-Run Equilibrium

A state in which all factors of production and economic inputs can be fully adjusted, and all market forces are balanced.

Increase in Demand

A situation where the quantity of a good or service that consumers are willing and able to purchase at a particular price rises.

Marginal Revenue

The additional revenue that a firm gains when it sells one more unit of a product or service.