Prohibition of Hachana and Making an Eruv Tavshilin

If one cooks on Yom Tov for a weekday that follows it – what is the din?

If one cooks on Yom Tov for Shabbos that follows it – what is the din?

According to most Rishonim: Is it permitted to cook on Yom Tov for Shabbos – when done close to night?

If he made an Eruv Tavshilin – it is permitted.
It is forbidden.
It is permitted.
It is permitted – since it’s possible that guests will come who will benefit from it.

What are the reasons why the Eruv Tavshilin was enacted?

If someone placed an Eruv Tavshilin on a particular Erev Yom Tov – may he rely on it l’halacha for the next Yom Tov?

He is required to place a new Eruv Tavshilin in its place.
If something remains from that Eruv – he does not need to place a new one in its place.
Lechatchila – he should place a new Eruv; B’dieved – the previous Eruv suffices.
If something remains from the previous Eruv – he should not place a new one in its place.

If one does not intend to cook on Yom Tov for the Shabbos which follows it – is he required to place an Eruv Tavshilin?

He does not need to place one.
He should place one, but without a bracha.
He does not need to place one. But if he does place it – he does not recite a bracha.
He should place an Eruv, and recite the bracha as well.

If the Eruv was eaten from on Yom Tov itself – what is the din?

If some of the bread remained – one is permitted to cook for Shabbos.
If a kezayis amount of the Eruv remains – one is permitted to cook for Shabbos.
If something remains from the Eruv – one is permitted to still cook for Shabbos.
Answers 2 and 3 are correct, but it depends according to which opinion.

In the case where one wants to shecht on Yom Tov for Shabbos which follows it – what is the din?

Lechatchila – he should mention the “shechita” within the text of the Eruv; B’dieved – it doesn’t withhold its effectiveness.
He is required to mention the “shechita” within the text of the Eruv.
He is not required to mention the “shechita” within the text of the Eruv.
Answers 2 and 3 are correct, but it depends according to which opinion.

Who does not fulfill their obligation with the Eruv placed by the city’s Rav?

Through whom should the Eruv be “granted a share” with – for the Eruv to be effective for all the city’s inhabitants?

Through someone else who is not the Rav’s family member.
Through someone else. B’dieved – it is effective if done by one of his family members who is not a child.
Through someone who is the age of Bar Mitzvah.
Through one of the city’s inhabitants.