The Factor Most Directly Responsible for Making a Black Hole

question 21

Multiple Choice

The factor most directly responsible for making a black hole invisible is its

• A) color.
• B) mass.
• C) surface escape velocity.
• D) size.
• E) none of these

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Definitions:

Cork Cambium

A layer of tissue in plants that produces cork cells to replace or augment the plant's outer epidermis, contributing to the bark's development.

Secondary Phloem

The part of a plant's vascular system that transports nutrients and is formed after the primary growth phase.

Cork

Outer covering of the bark of trees; made of dead cells that may be sloughed off.

Sieve-Tube Members

Specialized elongated cells in the phloem of vascular plants, which transport sugars and other organic nutrients.