The points A and B have position vectors i + 7j + 2k and -5i + 5j + 6k respectively, relative to an origin O.

(i) Use a scalar product to calculate angle AOB, giving your answer in radians correct to 3 significant figures. [4]

(ii) The point C is such that \(\overrightarrow{AB} = 2\overrightarrow{BC}\). Find the unit vector in the direction of \(\overrightarrow{OC}\). [4]