find `AuuB, AnnB and Ann(BuuC) where A = { p,q,r,s}, B = {q,r,s,t} and C = {q,r,t}`

List the sets A,B and C , given that, A cupB={p,q,r,s}, A cupC ={q,r,s,t}, A cap B={q,r}, A cap C={q,s}.

If A={p,q,r,s}, B={r,s,t,u} and C={p,q,r}, then (A-B)-C is .........

A = {P,Q,R,S,T,} B={R,T,V} Write A cap B

If P={p,q,r,s,t,u} and Q capR={q,r,v,w} , find (P-Q)cup(P-R)

If P={p,q,r,s,t,u} and Q capR={q,r,v,w} , find (P cup Q) cap(PcupR)

if P,q, r, s in R such that p r= 2 ( q+ s) then

If p, q, r are in A.P., q, r, s are in G.P. and r, s, t are in H.P., prove that p, r, t are in G.P.

Lines p,q and r are concurrent.Also lines p, s and t are concurrent.Is always true that the lines q,r and s will be concurrent? Is it always true for lines q,r and t?