How did the balance of power between spain and the united states change.

Which is an advantage to using nonrenewable resources? a. they can be cheaper. b.they can have a lower impact on the environment. c.they can be used up rapidly. d.they can contribute to global warming.

Ben is interested in using a source that provides original research, current and developing trends and experts within specific fields. which source should he use?

Two technicians are discussing how to test a car's exhaust by holding a small piece of paper within an inch of the tailpipe mouth. technician a says that if the paper is vibrating due to a "puffing" output from the tailpipe, this signals a smoothly running engine. technician b says that if the paper is being drawn toward the tailpipe, this could indicate burned exhaust valves. who is correct? a. technician b b. both technicians a and b c. technician a d. neither technicians a or b