When in doubt, go to the source! Miranda v Arizona. Paste and copy the website below into your browser.
www.law.cornell.edu/supct-cgi/get-us-cite?384+436 - 12k
It lays out the Supreme Court's holding (decision) very well right on the first couple of pages. You should be able to answer the questions pretty easily from there.
If you click on the purple box above the holding of the case that says "opinion" you can read the opinion of Justice Warren, who wrote the majority decision. It is also important to read the "dissent." Those usually lay out the scenario that goes against what the majority decided. Those may help you with your questions.
I'm not trying to be curt with my answer, but you may be able to use that resource to write your entire essay.
A person must be IN CUSTODY AND BE INTERROGATED before Miranda rights apply. If one is missing, no miranda must be given.
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