Yes.
false apex
Yes the given segments would form an isosceles triangle
Yes the given segments would form an isosceles triangle
Yes. What you should watch out for is that, to form a triangle, none of the segments should be longer (or as long as) the other two segments combined. Just check whether the longest segment is longer than the sum of the other two - if it is, then you can't form a triangle.
Yes they could.
No, it could not. A triangle cannot have a perimeter of length zero.
Yes
true
Yes
Yes.
Yes.
No, they could only form a straight line.
Yes.
false apex
Yes the given segments would form an isosceles triangle
Yes the given segments would form an isosceles triangle