Aresearcher finds that people who own more than two cars have bigger homes, more garage space, and make more money than people who own only one or two cars. therefore, the researcher concludes that having more than two cars causes people to have homes with bigger garages. according to cook and campbell's types of evidence, the researcher failed to eliminate:

An externality can be created by a. people working at a production job and enjoying their work b. a production activity but not a consumption activity c. a consumption activity but not a production activity d. a production activity or a consumption activity externalities a. are always positive, and an example is flu vaccinations b. are always negative, and an example is the pollution created by trucks c. can be negative or positive. logging has a negative externality, and education has a positive externality d. can be negative or positive. a negative externality is having to go to school when you would rather go to the beach, and a positive externality is spending time with your friends

Brainliest to who answers! what is the function of a purchasing cooperative, or co-op?

Name that largest artificial lake built in the 11th century