How do humans communicate with the Earth?

Which characteristic is typical of a young river? A. Is in a wide, U-shaped channel B. Has a low stream gradient C. Is near headwaters D. Has many tributaries

A scientist makes a discovery that suggests a hominid species created and used relatively sophisticated tools. The scientist decides to publish his findings.

Which of the following is a characteristic that can be applied to both living and non-living things

How do we know that some layers of the earth are solid and some are liquid?

the condition known as heartburn is most often caused by acid regurgitation from the stomach into the esophagus. Some of the drugs that treat heartburn work by decreasing the secretion of acid by the cells of the stomach.

For a scientific theory to be valid, which of the following must be true? A. It must be well tested. B. It must be widely accepted. C. It must explain the observable facts. D. All of the above

oxygen has eight protons in it's nucleus. Calculate the number of neutrons and electrons in a neutral oxygen-16 atom.

What are antibodies to defend the cell against "invaders"

Which of the following are characteristics of heterogeneous mixtures? distinguishable components evenly distributed components particles too small to be seen with a microscope components in varying proportions particles that may settle

You have a yellow pea, but you do not know if it is heterozygous (Yy) or homozygous. When you perform a test cross to a green recessive pea (yy), you observe that half the offspring have yellow peas and half have green peas. What can you conclude? a.