Hi, I just want to make sure I am doing this right:

Question

Construct a relation on the set {a, b, c, d} that is
a) reflexive, symmetric, but not transitive.
b) irrreflexive, symmetric, and transitive.
c) irreflexive, antisymmetric, and not transitive.
d) reflexive, neither symmetric nor anti symmetric, and
transitive.
e) neither reflexive, irreflexive, symmetric, antisymmetric,
nor transitive.

What I got is
a) a and b have a common grandparent
b) ab ≥1
c) a = b + 1
d) a mult. of b
e) not sure

and are there more examples other than this?

Thank you!