Look at the picture down below to answer the question!
>>Select the 2 that apply.
Q: An unsaturated hydrocarbon is represented by which structural formula(s)?
>>Choose two from the picture below that matches with the question above!

A and D

Explanation:

unsaturated hydrocarbons have double or triple bonds

it's c. elements are placed in rows based on how may valencies electrons have.

geosphere and hydrosphere.

this is because the geosphere has to do with geological events, while the hydrosphere controls all water on earth.