Current Searches for Extraterrestrial Intelligence Use Radio Telescopes at Wavelengths

question 19

Multiple Choice

Current searches for extraterrestrial intelligence use radio telescopes at wavelengths

• A) which must be shorter than the local wavelengths emitted by Earth s atmosphere
• B) which must be longer than the radio wavelength noise naturally emitted by our galaxy
• C) Both conditions a and b above must be fulfilled.
• D) Wrong! Visual light wavelengths are used because they are blocked by dust between the stars.

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Definitions:

Socially Optimal Quantity

The level of production that maximizes societal welfare, often considered at the point where marginal cost equals marginal benefit.

Marginal Social Cost

The total cost to society of producing one additional unit, including both private costs and any external costs.

Marginal Social Benefit

The extra advantage to the community that comes from creating or using an additional unit of a product or service.

Pollution

It refers to the introduction of harmful substances or products into the environment, causing adverse effects on living beings and ecosystems.