Teacher:In this task, you need to answer the given multiple-choice question on the physics. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.
Teacher: Now, understand the problem? Solve this instance: Problem: what is the distance between two parallel chords of length 32 cm and 24 cm in a circle of radius 20 cm ?
Options: ['a ) 1 or 7', 'b ) 3 or 21', 'c ) 4 or 28', 'd ) 2 or 14', 'e ) 5 or 14']
Student:
c