An epidemiologist, dr. stu d. hertz, will study the association between smoking status and serum cholesterol level. he will measure cholesterol in random sample of smokers and a separate random sample of nonsmokers. he thinks that smoking is associated with higher cholesterol levels. the overall mean cholesterol level in the population is 215 mg/dl. which null hypothesis should dr. hertz test?

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

the rocks are classified by the geological process they are formed by. the three main groups of rocks are igneous, metamorphic, and sedimentary. minerals are not they are classified under the chemical classes they are in. these groups include silicates, sulfates and carbonates.