What are the following sets?
a) ({a,b}∪{a,c})×({a,c,d}∩{b,d,e})
b) {a, {b, c}} ∩ {b, {a, c}}
{a,b}∪{a,c} = {a,b,c}
{a,c,d}∩{b,d,e} = {d}
{abc}×{d} = {ad,bd,cd}
In part b, since the two sets have no elements in common, the intersection is empty.