Answer:
a)  {a,b} , {c,d} , {e,f,g},{a , b } = {(a,a) (b,b) (a,b) (b,a)},{c , d } = {(c,c) (d,d) (c,d) (d , c) } ,{e,f,g} = {(e,e) (e,f)  (f,e) (e,g) (f,f) (f,g) ( g,e) (g,f)(g,g)}  
b) { (a,a)(b,b)(c,c)(c,d)(d,c)(d,d)(e,e)(e,f)(f,e)(f,f)(g,g)
c)  {(a,a)(a,b)(b,b)(b,a)(a,c)(c,a)(b,c)(c,b)(c,c)(d,a)(a,d)(b,d)(d,b)(d,c)(c,d)(d,d)(c,c)(c,f)(f,c)(f,f)(c,g)(g,c)(f,g)(g,f)(g,g)
Step-by-step explanation:
a) {a,b} , {c,d} , {e,f,g}
   {a , b } = {(a,a) (b,b) (a,b) (b,a)}
   {c , d } = {(c,c) (d,d) (c,d) (d , c) } 
   {e,f,g} = {(e,e) (e,f)  (f,e)  (e,g) (f,f) (f,g) ( g,e) (g,f) (g,g)}  
b) {a} ,{b},{c,d} ,{e,f},{g}
      { (a,a)(b,b)(c,c)(c,d)(d,c)(d,d)(e,e)(e,f)(f,e)(f,f)(g,g)}
c)  {a,b,c,d},{e,f,g}
    {(a,a)(a,b)(b,b)(b,a)(a,c)(c,a)(b,c)(c,b)(c,c)(d,a)(a,d)(b,d)(d,b)(d,c)(c,d)(d,d)(c,c)(c,f)(f,c)(f,f)(c,g)(g,c)(f,g)(g,f)(g,g)