What is genetic variation?

Although respiratory organs vary across different organisms, they all contain respiratory surfaces that have a large surface area and are extremely thin. explain why having an extremely thin respiratory surface with a large surface area is advantageous for the process of gas exchange

Which of the following statements is true? a. most heat energy is easily recovered and used for useful actions. b. friction causes molecules to vibrate more slowly. burning air and gasoline in an c. engine changes chemical energy into mechanical energy. it is impossible to d. change mechanical energy into mechanical energy.

Choose one literary selection from this semester in which you think the setting has a great impact on the work. in a full paragraph name the work, describe the setting, and explain why it is so important to the overall story or poem.