It’s science but pls help me

Awaiver of the requirement for documentation of informed consent may be granted when: the investigator has no convenient place to store signed consent forms separate from the research datathe only record linking the subject and the research is the consent document and the principal risk is a breach of confidentiality. potential subjects might find some of the research questions embarrassing, personal, or intrusivethe subjects are literate in their own language; however, they do not read, write, or speak english

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

How does danae feel about petraeus