ABCDA is a con cyclic quadrilateral of a circle ABCD with radius r and centre at O If AB is the diam...........

Quantitative Aptitude (CDS) Coordinate Geometry

ABCDA is a con-cyclic quadrilateral of a circle ABCD with radius r and centre at O. If AB is the diameter and CD is parallel and half of AB and if the circle completes one rotation about the centre O, then the locus of the middle point of CD is a circle of radius

$\frac{3r}{2}$