Recently, Astronomers Have Observed Stars and Other Objects That Orbit

question 20

Multiple Choice

Recently, astronomers have observed stars and other objects that orbit the center of the Milky Way Galaxy farther out than our Sun, but move around faster than we do. How do astronomers think such an observation can be explained?

• A) all these faster-moving objects must be escaping from the gravity of the Milky Way and will soon be lost to our Galaxy
• B) each of the faster-moving outer objects must be the result of a supernova explosion (giving them extra speed)
• C) it is the Sun that is moving too slowly because of a collision billions of years ago; the outer objects are really moving at the appropriate speed for their distance from the center
• D) there must be a great deal of invisible dark matter outside the orbit of the Sun whose gravitational pull explains the faster motions we see out there
• E) no one can come up with any explanation for this puzzling observation

Recognize the role of government in building infrastructure and managing economic policies for development.

Assess the effectiveness of export promotion policies and industrial policies in economic development.

Identify the relationship between a country's development level and its economic structure (including its agricultural output).

Explain the impact of capital availability on labor productivity and economic growth.

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Definitions:

Risk Premium

The additional return expected by an investor for holding a risky asset, over and above the risk-free rate.

Semi-Strong Form

A form of the Efficient Market Hypothesis suggesting that stock prices reflect all publicly available information, making it impossible to consistently achieve higher returns.

Strong Form Efficient

A hypothesis stating that all information, both public and private, is completely reflected in stock prices, meaning no investor can achieve higher returns with specific information.

Weak Form Efficient

A market efficiency theory stating that all past trading information is already reflected in stock prices, and that technical analysis cannot consistently produce excess returns.