The sixth age shifts Into the lean and slippered pantaloon

The sixth age shifts Into the lean and slippered pantaloon,
With spectacles on nose and pouch on side, His youthful hose, well saved, a world too wide
For his shrunk shank; and his big manly voice,
Turning again toward childish treble, pipes And whistles in his sound.
(a) Which is the stage of man’s life that the poet describes here?
(b) Give the meaning of ‘shrunk shank’.
© Why does his voice again turn ‘toward childish treble’?

(a) It is the sixth stage of life.
(b) It means that the calf muscles of the legs have weakened and shrunk due to old age and the legs have become thin and weak.
© Due to old age, the vocal chords also weaken considerably and the manly voice turns into a childish shriek.