Chapter 9.5, Problem 48E

t the ordered pairs in the equivalence relations produced by these partitions of $\left\{a,b,c,d,e,f,g\right\}$.

a) $\left\{a,b\right\},\left\{c,d\right\},\left\{e,f,g\right\}$

b) $\left\{a\right\},\left\{b\right\},\left\{c,d\right\},\left\{e,f\right\},\left\{g\right\}$c) $\left\{a,b,c,d\right\},\left\{e,f,g\right\}$d) $\left\{a,c,e,g\right\},\left\{b,d\right\},\left\{f\right\}$

A partitionP₁is called arefinementof the partitionP₂if every set inP₁is a subset of one of the sets inP₂.