Which of the Following Is Not an Observed Characteristic of the Cosmic

question 22

Multiple Choice

Which of the following is not an observed characteristic of the cosmic microwave background?

• A)It has a perfect thermal radiation spectrum.
• B)It contains prominent spectral lines of hydrogen, the primary chemical ingredient of the universe.
• C)Its temperature is a little less than 3 Kelvin (3 degrees above absolute zero).
• D)Its temperature is the same everywhere, except for small variations at the level of 1 part in 100,000.

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Definitions:

Cornea

Clear, protective covering at the front of a vertebrate eye; helps focus light on the retina.

Lens

A transparent structure in the eye that focuses light rays onto the retina, allowing for clear vision.

Dim Light

A low level of illumination, often insufficient for clear vision without adaptation or additional light sources.

Rods

Photoreceptor cells in the retina of the eye that are sensitive to low light levels and responsible for black-and-white vision.