The following vectors contain an unknown constant k. u= (1,1,k) v= (k,1,2) w= (1,k,2) (a) Are there any values of k for which u and v are parallel? (b) Are there any values of k for which v and ware parallel? (c) Are there any values of k for which u and v are orthogonal? (d) Are there any values of k for which wis orthogonal to both u and v?