should use

Question 2

んです
(n des)

Answer 2

To explain something that someone doesn’t know.
To declare/or confess something

Question 3

んですか

Answer 3

hey, I want to know, hey,would you explain,

Question 4

いいえ
(いや)

Answer 4

no, we use iya because iie is to long
(can use ie for more polite way)
(iya isnt that polite)

Question 5

で

Answer 5

used at the end of a sentence when talking about a location . Or where