In 1979, iranian militant groups took hostage in tehran.
a. 52 americans
b. american students
c. ayatollah khomeini
d shah mohamad reza pahlavi

   A. 52 Americans.

Explanation:

  Known as the Iran hostage crisis, it was a diplomatic standoff that lasts 444 days. A group of Iranian college students supporters of the Revolution held in that country took the U.S. embassy in Tehran. It is up to to this day the longest hostage crisis.

  They did this in response to what they saw as American complicity with the former Shah of Iran Reza Pahlavi who was accused of committed crimes to Iranian civilians. The U.S. admitted him for cancer treatment and gave him asylum. But Iran demanded his return to stand for trial. With the negativity of the U.S. the Revolution decided to took the embassy with 52 American diplomats and citizens inside.

  I hope this answer helps you.

health care plans in the united states having high costs because they are focusing on providing quality programs for different groups of individuals. the quality of the service is based on money flow received from the members. without this investment, couldn't be possible a constant scientific searching to prevent death and illness caused because of low levels of health investigation. currently, the complaints are not about the highest cost, but about the coverage and benefits to access the necessary health services required by the members.  

besides, if a global health system is established the quality levels will fall down because of the standardized of the health. the access to care will increase but the quality will be low because it depends on the money invested.

a. theta waves. this is because the person is in a light sleep which means the brain waves would show these kind of waves.