$16-129.$ The man stands on the platform at O and runs out towards the edge such that when he is at A$,$y$=5$ft$,$ his mass center has a velocity of $2$ft$//$s and an acceleration of $3$ft$//$s$^(2),$ both measured relative to the platform and directed along the positive y axis. If the platform has the angular motions shown, determine the velocity and acceleration of his mass center at this instant.

In addition to the acceleration, find all of the forces on the man. Calculate the kinematics by using Transport Theorem to differentiate the position vector with a variable distance y $($i$.$e$.$ don$$t substitute in y$=5$ ft until after differentiating$),$ and noting that the relative velocity of $2$ ft$/$s and relative acceleration of $3$ ft$/$s$2$ are $$ and $,$ respectively. Assume the man$$s mass is $70$ kg$.$