(Hand by written ans)What radius of the central sheave is necessary to make the fall time exactly 3 s, if the same pendulum with weights at R=80 mm is used? (data if needed from calculations - h = 410mm, d=78.50mm, m=96.59 g)

(Multiple options of the answer - 345.622 mm, 117.75 mm, 43.66 mm, 12.846 mm, 1240.804 mm, 35.225 mm)