Let the vectors be p=⟨t,2t,3⟩, q=⟨1,−t,6⟩ and r=⟨2,t2,0⟩, where t is a real parameter.
(i) Determine all value(s) of t for which p is perpendicular to q.
(ii) For the value(s) of t obtained in part (i), examine whether q is perpendicular to r and justify your conclusion.
(iii) Find all real value(s) of t for which the three vectors p,q and r are pairwise perpendicular.