In the given diagram, the points a, b, and c lie on a circle whose center is o. boc is a diameter of the circle. the following set of premises is relevant to the investigation of the given geometric diagram: i. the radii of a circle are of equal length. ii. angles opposite to equal sides of a triangle are equal. iii. the sum of the angles of a triangle is 180°. with reference to the diagram, which conclusion can be drawn correctly from the premises? a) ac = co b) oa + ob + ab > ∠bac c) m∠aco < 45° d) m∠bac = 90°