Whp did the maya building observatories ta the top of their pyramids.

97 points what types of changes have been made in the united states to protect people from earthquakes? a. communities are no longer located along fault lines. b. building codes ensure that structures can withstand shaking. c. warnings go off when an earthquake is expected, and people evacuate the area. d. barriers have been built to prevent flooding by a tsunami.

Which of the following did the founding fathers see as a benefit of the federal structure (federalism) of government? a.) all power is concentrated in the national government. b.) the power is divided between national and state governments. c.) all the power is concentrated in the state and local governments. d.) the power is divided between the people and the government

Before they can be published, scientific papers must be peer-reviewed. this means that: a) some other scientific experts read the papers and guarantee that they are true.b) some other scientific experts read the papers and provide quality control by eliminating many mistakes.c) an editor reads the papers, to make sure that all the semicolons are in the correct places.d) everyone in the world is given the opportunity to comment on the papers through a specially maintainedblog.e) government bureaucrats read the papers, to be sure that the papers do not insult the political positions ofthe current officeholders.