Write about finding an undiscovered planet

What is one major role of political parties in u. s. politics

Acase study allows a more detailed look at the life of a single subject than any other study

What is the difference between an observational study and an​ experiment? choose the correct answer below. a. in an​ experiment, a treatment is applied to part of a population and responses are observed. in an observational​ study, a researcher measures characteristics of interest of a part of a population but does not change existing conditions. b. in an​ experiment, a treatment is applied to an entire population and responses are observed. in an observational​ study, a researcher measures characteristics of interest of an entire population but does not change existing conditions. c. in an​ experiment, a researcher measures characteristics of interest of a part of a population but does not change existing conditions. in an observational​ study, a treatment is applied to part of a population and responses are observed. d. in an​ experiment, a researcher measures characteristics of interest of an entire population but does not change existing conditions. in an observational​ study, a treatment is applied to an entire population and responses are observed.