Probably the MOST Difficult Factor to Estimate in the Drake

question 14

Multiple Choice

Probably the MOST difficult factor to estimate in the Drake equation is

• A) R^*, the rate at which solar-type stars form in the Galaxy.
• B) f_p, the fraction of stars that have planets.
• C) n_e, the number of planets per solar system that are Earthlike (suitable for life).
• D) L, the lifetime of a technologically advanced civilization.

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Definitions:

Tarsals

A group of seven bones in the foot situated between the lower leg bones (tibia and fibula) and the metatarsal bones, playing a key role in the structure and function of the foot.

Axial Skeleton

The part of the skeleton that consists of the bones of the head and trunk of a vertebrate.

Appendicular Skeleton

Part of the skeleton that includes the bones of the limbs and the pectoral and pelvic girdles, facilitating movement.

Cavitiy

A hollow space within the body or one of its organs; however, the correct spelling is "cavity."