What event caused United States to help cuba gain freedom from spain​

The specific department of health and human services (hhs) regulations that apply to research with children are known as: subpart b: additional protections for children involved as subjects in researchsubpart a: the common rulesubpart d: additional protections for children involved as subjects in researchsubpart c: protections for children in research

Where do the majority of cases heard by the supreme court originate?

What conflict ended the false doctrine of "states rights"