Are these sentences correct with the given meanings:
1-Most of my best friends will be at the party. However I am not sure two of them will be there.
(I do not know if two specific friends will be there or not).
2-Most of my friends said they will come to help me. However I am not sure two of them will show up.
(I am not sure if EVEN two of them will show up.)
3-My students are all taking the exam. I don't know if five of them will pass it or not.
Meaning a:I don't know if five specific students will pass it or not. I have doubts about five specific students passing it.
Meaning b: I don't know if even five of them will pass it. I think that maybe fewer than five people will pass the exam.