Question : The length of the common tangent PQ for two circles touching externally is 16 cm. If the radius (OP) of the bigger circle is 20 cm, then the radius (RQ) of the smaller circle is:

Question : Two circles of radii 15 and 18 cm touch each other externally. What is the length (in cm) of the direct common tangent to the two circles?

Question : $\overline{\mathrm{CT}}$ is a tangent to a circle at the point $\mathrm{T}$ on the circle. Chord $\overline{\mathrm{AB}}$ of the circle is extended to meet the tangent $\overline{\mathrm{CT}}$ at the point $\mathrm{C}$. If $\mathrm{m}(\overline{\mathrm{AB}})=3 \mathrm{~cm}$

Question : Two circles touch each other internally. Their radii are 3 cm and 4 cm. What is the length of the biggest chord of the circle with radii of 4 cm which is outside the inner circle?

Question : Two circles touch each other externally at any point C. PQ is the direct common tangent to both the circles touching the circles at point P and point Q. If the radii of the circles are 36 cm and 16 cm, respectively, then the length of PQ is: