Which of the following is a type of wave that does not need a medium though which to travel? equilibrium longitudinal amplitude transverse

I'm pretty sure the answer is A. I am taking the test right now and that seems to be the only logical answer.

I will update if I get it correct.

So I got it wrong :( it is not A or D. My next thought would be C though

the precambrian aged rocks could be found in australia. australia is a region that has a lot of ancient civilization history from million years ago. in this region, there are a lot of recognizable fossils buried in its land which is considered a precambrian-aged rocks

the awnser is a

it is not b or c