Doctors are interested in seeing if lifting weights to alleviate back pain is effective. twenty five volunteers are asked to rank their level of pain on a scale from one to ten. for the next two months, they then exercise for 2 months with a physical therapist. the volunteers focus on different weight lifting exercises that strengthen the back. twenty five volunteers are again asked to rank their level of pain on a scale from one to ten. was the amount of pain less after completing the exercises? what type of test would they conduct to test this claim? a) one meanb) comparing proportions from 2 independent samplesc) comparing means from dependent samplesd) comparing proportions from dependent samplese) one proportionf) comparing means from 2 independent samples

Which scenarios are most effectively explored by conducting an experiment? there is more than one correct answer. select all that apply. researchers want to study the effectiveness of a particular drug for treating migraines. they want to know which dosage of the drug yields the best results with the least side effects. to ensure fair results, the researchers want to ensure that participants and dosage administrators do not know which dosage participants receive. a teacher wants to plan a class fieldtrip and quickly determine where students prefer to go for the class fieldtrip. a car mechanic wants to know which of two engine brands makes better-performing engines. he wants to test the engines in identical situations and rate their performance in a way that can be fairly measured. a chemist studies the properties of a metal compound. she wants to know how the sample size of the metal affects its ability to conduct electricity. she wants to conduct the research in a controlled environment to minimize bias. a realty company wants to know the average income of its clients. the company wants to gather data income from current clients.