help with pendulum swing

[vtech]

Jack, who weighs 653 N, swings from a cliff at the end of a convenient vine that is 26 m long. From the top of the cliff to the bottom of the swing, he descends by 3.2 m. The vine will break if the force on it exceeds 950 N.

(a) Does the vine break? yes / no
(b) What is the greatest force on the vine during the swing? ____Newtons
(c) At what angle does it break, if it breaks?

[Tide]

This should be in the homework section.

What exactly have you done so far?

[Doc Al]

You already posted this problem elsewhere: http://www.physicsforums.com/showthread.php?t=47461

Please do not double post!