Read the paragraph, and then answer the question.
Coal is a black, hard substance formed from the remains of living things that existed a long time ago. The remains were buried and exposed to pressure and temperature underneath Earth’s surface. Over time, these remains solidified.?
Coal is formed from the remains of living things that existed a long time ago and were buried and exposed to pressure and temperature. Over time, these remains solidified.
Based on the paragraph, what is coal formed from and how does it solidify over time?