Given three collinear points A, B, C, name all the lines-segments they determine.

1 If B lies between A and C and AC = 10 cm, BC = 5 cm, what is AB².
2 In the figure, POQ is a line, ∠ POR = 4x and ∠ QOR = 2x. Find the value of x.
                              4 In the figure, OA and OB are opposite rays.
(i) If ∠ BOC= 75°, find ∠ AOC
(ii) If ∠ AOC= 110°, find ∠ BOC.
                        5 In the figure, lines AB, CD and EF intersect at O. Find the measures of ∠AOE, ∠EOD, ∠BOD and ∠COF.