What's the disadvantage of barter system

One similarity between the student non-violent coordinating committee (sncc) and the southern christian leadership conference (sclc) is that they both

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

What policy did "jim crow" laws put in place? black codes integration segregation 2. the supreme court case that established the doctrine of "separate but equal" was dred scott v. sandford plessy v. ferguson brown v. board of education 3. the supreme court case that overturned the doctrine of "separate but equal" wasdred scott v. sandford plessy v. ferguson brown v. board of education