What is an instrument used to detect earthquakes?

Which of the following energy sources is not an example of renewable energy? a. a wind turbine farm b. a clean-burning, coal-fired electric plant c. a hydroelectric dam d. a solar panel mounted on a home

Which revelation resulted from the observation of the spectrum of different galaxies? a. there were more galaxies whose spectrum was blueshifted b. there were no galaxies whose spectrum was redshifted c. there were more galaxies whose spectrum was redshifted d. there were no galaxies whose spectrum was blueshifted

Which of teh following would explain the importance of the trans-siberian railroad to russia's economy? (schoology test)