Can someone pls help me?

The grooves or folds of the brain are called

Which of the following describes a compound? (hint: carbon and oxygen bo a. a piece of pure carbon, containing only carbon atoms b. oxygen gas surrounding a solid piece of carbon c. a substance made of two oxygen atoms for each carbon atom carbon and oxygen atoms mixed without being bonded together

Mary is conducting an experiment on how pollution affects plant growth. how can she ensure that her data are reliable?