Does the sun shine for more, less or equal amounts for the start of spring?

Tropical rain forests support more species per unit area than any other terrestrial ecosystem. what is one way rain forests are important to the health of the biosphere?

What do transitional fossils best support?

Chronic obstructive pulmonary disease (copd) makes it difficult for the respiratory system to deliver oxygen to the lungs. the scientist wants to use a computer simulation to model how copd affects heart rate and respiratory rate during exercise. she will compare the results of the simulation to the results she gathered in her previous study. which of the following would be an appropriate dependent variable for the new study?