Which best describes the amount of earth's total water supply that is usable freshwater?

Compare the depth of field when focusing with low power and high power. which power has the greater depth of field?

Which of the following is not a food produced in rainforests? a) coffee b) cocoa c) avocados d) wheat

What molecules will be best used to compare different species with the exact same sequence of amino acids? why would two species have the same protein even if the molecules in question is different? (hint: transcription to translation to protein).