Ответ:

\(A=\{15,30,45,60,75,90\}\), \(B=\{10,20,30,40,50,60,70,80,90\}\).

\(A\cap B=\{30,60,90\}\).

\(A\cup B=\{10,15,20,30,40,45,50,60,70,75,80,90\}\).