Q: Answer the question

A student has two solid samples of the same substance. Which property do the substances most likely have in common?

A: density

Q: Answer the question

When animals use energy, what is always produced?

A: heat

Q: Answer the question

A scientist was examining a large boulder that was covered with lichens (a combination of fungi and algae). He chipped a piece of the rock and placed it under a microscope. He observed that the surface of the rock was breaking down underneath the lichen. Which was the scientist most likely observing?

A:
the effects of chemical weathering