Question : The radius of the two concentric circles are 17 cm and 10 cm. A straight line ABCD intersects the larger circle at points A and D and intersects the smaller circle at points B and C. If BC = 12 cm, then the length of AD(in cm) is:

Question : Chords $\overline{AB}$ and $\overline{CD}$ of a circle intersect inside the circle at point F. If $m(\overline{AF})=2.4$ cm, $m(\overline{BF})=1.8$ cm and $m(\overline{CD}) = 5.7$ cm, what is the length (in cm) of the longer of the two line segments, $\overline{CF}$ and

Question : Chords AB and CD of a circle intersect at E. If AE = 9 cm, BE = 12 cm, and CE = 3DE, then the length of DE(in cm) is:

Question : The radii of two concentric circles are 34 cm and 50 cm. A and D are the points on a larger circle and B and C are the points on a smaller circle. If ABCD is a straight line and BC = 32 cm, then what is the length of AD?

Question : Two circles of radius 2.4 cm and 4 cm, respectively, have a common tangent. The distance between the centres of the two circles is 6.5 cm. If the common tangent does not intersect the line joining the centres, then find the length of a common tangent to the circles.