In this task, you need to answer the given multiple-choice question on geometry. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

[Q]: Problem: pr is tangent to a circle at point p . q is another point on circle such that pq is diameter of circle and rq cuts circle at m . if radius of circle is 4 units and pr = 6 units . find ratio of triangle pmr to pqr . 
Options: ['a ) 11 / 20', 'b ) 3 / 5', 'c ) 13 / 20', 'd ) 18 / 25', 'e ) 18 / 26']
[A]: c


[Q]: Problem: find the circumference and area of radius 6 cm . 
Options: ['a ) 113 cm ²', 'b ) 144 cm ²', 'c ) 154 cm ²', 'd ) 184 cm ²', 'e ) 194 cm ²']
[A]: a


[Q]: Problem: a circular well with a diameter of 2 metres , is dug to a depth of 4 metres . what is the volume of the earth dug out ? 
Options: a ) 26 m ³ , b ) 28 m ³ , c ) 44 m ³ , d ) 46 m ³ , e ) none
[A]:
c