Human activities such as fishing and game often cause an impact on the ecosystem
human waste enters other natural ecosystems where it can cause them to be unbalanced
You need to have the velocities of the P and S wave in order to solve the first problem. Those velocities depend on the rock through which they travel.
Because D is highlighted so it's correct don't argue, you don't need to know
Answer:
Observations are receiving knowledge of the outside world through our senses, or recording information using scientific tools and instruments.
Any data recorded during an experiment can be called an observation.
