Step 1:
What is the complement of set A' ? are elements or members of set A that are not in the universal set U.
Step 2
Set A = {g,y,m,n,a,s,t,i,c}
Universal set U = {a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z}
Step 3:
A' = {b, d, e, f, h, j, k, l, o, p, q, r, u, v, w, x, z}
Final answer
A' = {b, d, e, f, h, j, k, l, o, p, q, r, u, v, w, x, z}