A city in California has asked Professor Rodriguez to conduct an experiment on earthquake preparedness. Professor Rodriguez will assess the preparedness of a random sample of residents in the city and the city will mail out their annual brochure on earthquake safety. Then, 2 weeks later, he will again assess the preparedness of those residents. Right after the brochures are mailed, a large earthquake is reported in Japan. Which threat to internal validity does this pose?a. selection.
b. testing.
c. history.
d. maturation.

The people of are overwhelmingly arab but are divided by religion.

Which statement best completes the diagram of the ways the different branches of government can limit each other's powers?

Base your answer for this question on the statement below and on your knowledge of social studies.my fellow citizens, events in iraq have now reached the final days of decision. for more than a decade, the united states and other nations have pursued patient and honorable efforts to disarm the iraqi regime without war. that regime pledged to reveal and destroy all its weapons of mass destruction as a condition for ending the persian gulf war in 1991.…— president george w. bush, march 17, 200344 which action did president george w. bush take following this statement?