Let u=(2t)i+j+tk and v=i+tj−k, where t is a real parameter.
Answer the following questions.
(i) Find all real values of t for which u and v are perpendicular.
(ii) If the angle between u and v is 60∘, determine the possible value(s) of t.
(iii) For t=2, decide whether the angle between u and v is acute or obtuse and justify your conclusion.