How can drip irrigation method be used expain

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

Which groups of people most directly benefited from song innovations in the song dynasty‘s open border policy?

Suppose you are a freshmen in college and you have not declared a major. one reason you enrolled at your respective college was the school's vibrant social life. at the same time, you want to balance your academic life because you know that your grades will matter for graduate school or job applications.you decide to forgo partying for two hours to study for an upcoming economics exam. in your first semester's principles of economics class, you learn that the enjoyment you would have received from partying is an example of a(n)