Rocky mountain spotted fever is caused by

bacteria
a virus
rickettsia

*will mark brainliest to first correct answer* photosynthesis led to increasing levels during the later proterozoic eon? a. oxygen b. water c. carbon dioxide d. none of the above

Which of the following systems in absorbing oxygen and releases carbon dioxide

Which statement is true about the cell theory? a) it is well-supported by evidence. b) it is unchangeable and permanent.