The body is protected against harmful flu viruses by

Consider the diagram below, which represents components of the biosphere. what do the two arrows in the diagram most likely represent? a. radiation b. photosynthesis c. cellular respiration d. energy conversions will give to anyone who answers quickly

An easy way to calculate the amount of energy available at each level is to what?

Which greenhouse gas is emitted when burn fossil fuels for energy? a. nitrogen b. oxygen c. carbon dioxide d. helium