During which period of the paleozoic era did the largest mass extinction occur

Which of the following is true of all geographic locations on earth?

Some gamma ray bursts are hypothesized to come from mergers of neutron stars or black holes. if this hypothesis is correct, what else should we in principle be able to detect from such mergers? a. gravitiational waves b. x-ray bursts c. significant disruption of gas thousands of light-years away in the surrounding galaxy d. an "afterglow" of bright visible light, lasting for weeks

Although china’s total economic output, measured by gross domestic product (gdp), is third largest in the world, it is considered a developing nation. what is most likely the most important factor for this designation? a. china’s government spends money on things that do not benefit human development. b. china has a large population, so its gdp per person is only modest. c. china has a strong economy but weak literacy and school attendance rates. d. china’s high rates of disease offset the country's economic gains.