What did aristotle observe to him understand that earth is round ?
a, c,e

There are four observations that helped Aristotle to understand that Earth is round.

Explanation:

The Ships he observed appeared from to sail first behind the horizon, after then only the hull. We can see further standing on a higher standpoint. The ships again but also islands in the Aegean sea from a cliff.The Earth 's shadow caused the eclipse (lunar). He also observed that the shadow always looked circular.While travelling to south new constellations can be seen above the southern horizon. And as we travel more towards the south we see Polaris lower and lower.

Yes yes yes very good

Answer:

the statements that apply here about binary star system are

"have stars that might appear to wobble"

"often have one star that is brighter than other"

a binary star is a star system consisting of two stars revolving around their common barycenter. systems of two or more stars are called multiple star systems.