When Did a Planet Undergo Retrograde Motion in Ptolemy's Model

question 16

Multiple Choice

When did a planet undergo retrograde motion in Ptolemy's model of the solar system?

• A)When the deferent of a planet carried it closest to the Earth
• B)When the Earth passed the planet as they both orbited the Sun
• C)When the planet was dimmest and most distant
• D)When the planet was on the part of its epicycle that was nearest the Earth

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Definitions:

Inguinal Region

The area of the lower abdomen just above the leg crease, near the groin.

Popliteal Region

The area behind the knee where the thigh and calf meet, containing nerves, blood vessels, and muscles.

Cervical Region

Refers to the neck portion of the spine, comprising seven vertebrae that support the head and allow for its movement.

Medullary Cord

Part of the lymph node's internal structure composed primarily of B lymphocytes and plasma cells.