If a point P has co-ordinates (0, $$-$$2) and Q is any point on the circle, x² + y² $$-$$ 5x $$-$$ y + 5 = 0, then the maximum value of (PQ)² is :

If two parallel chords of a circle, having diameter 4units, lie on the opposite sides of the center and subtend angles $${\cos ^{ - 1}}\left( {{1 \over 7}} \right)$$ and sec^$$-$$1 (7) at the center respectivey, then the distance between these chords, is :

The radius of a circle, having minimum area, which touches the curve y = 4 – x² and the lines, y = |x| is :

Equation of the tangent to the circle, at the point (1, −1), whose centre is the point of intersection of the straight lines x − y = 1 and 2x + y = 3 is :