National parks reduce the human impact on land by a. permitting limited human development. b. cleaning up litter c. preventing human development d. preventing companies from polluting on public lands

a researcher conducts an experiment on the secretion of a particular hormone in mice. scientists inject mice with a substance that stimulates the production of the hormone. the scientists then test the levels of hormones produced by the mice. the tool used to measure the hormones consistently detects the levels at 10 points lower than the actual hormone levels in the mice. this tool makes measurements, but the measurements aren't .

explanation:

no u

answer australia and antarctica;