The skirt looks better. Jeans are a no-no for interviews. See for more interview attire tips.
A rope.
I used to hire people as a fast food manager. Honestly jeans would be fine as long as there is no holes and they aren't dirty or covered in paint or anything. What mattered most to me was that you were on time or early and that you were pleasant, honest, and respectful. A good smile is always good in a public service job. Remember shake hands before and after, look the interviewer in the eye, don't be late! And good luck to you!
I think jeans would look more presentable for the job interview. But most importantly wear something that you are comfortable in . Good luck ! :)
Sorry I don't know.