What is this solid made of?

There are sediments at the bottom of this lake that have accumulated over centuries.

There are many things placed in my room.

We should always remember the power of Kannon in difficult times.

Protists are being studied in a branch of biology.

Arthropods are a large group of animals that include insects, spiders, shrimp, and crabs.

Carbohydrates are important as a source of energy.

The ejecta from volcanoes help to elucidate the geological history of the Earth.

This structure has existed for centuries.

In chemistry class, I learned about basic oxides.