The second is the correct answer ^.^.
Geologists use these records to establish the structure of Earth's interior. The two principal types of seismic waves are P-waves (pressure; goes through liquid and solid) and S-waves (shear or secondary; goes only through solid - not through liquid).
Sodium is a solid and a liquid
Hope this helps
Answer:Sunlight
Explanation:
Sunlight is a physical factor that really determine the amount of plant life available in an ecosystem. Plants depend on sunlight to produce their own food via photosynthesis. Hence in the absence of sunlight, the amount of plant life will drastically reduce in a given ecosystem. Sunlight is indispensable for plant growth.