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According to the aztec history, how did the aztecs know where to build their new city of tenochtitlan? why was this a good location?

Pj conducts an experimental study on the effects of soft music during high stakes science testing. he randomly assigns students at the school. in one condition he does not provide music for testing while in the other group he does provide the music. he administers a pretest at the beginning of the year and a posttest at the end of the year. pj’s design is best described as a: a.static group comparisonb. pretest-posttest control group designc.control-group-time-series designd. nonrandomized control-group pretest-posttest design

The form the boundary between north and south china. a. himalayan mountains c. change river b. xi river d. qinling shandi mountains