What causes the retrograde motion of mars? a.) mars passes earth since it orbits the sun faster b.) mars moves backwards in its orbit for a brief time c.) earth moves slower when it approaches mars in its orbit d.) earth passes mars in its orbit since it orbits the sun faster

(B) Mars moves backwards in its orbit for a brief time.

Explanation: As the Earth moves forward in its orbit, Mars will appear to slip backward compared to its more common eastward march across the sky.

the species living around the vents are especially good at dispersal.  

deep-sea vent originates on the floor of the ocean when seawater circulates through hot volcanic rocks, usually situated where the new oceanic crust is being produced.  

biological dispersal refers to the movement of species from their location of birth to their site of breeding, or from breeding site to another. similarly, the oceanic dispersal refers to the movement of the species from one land mass to another by sea crossing.