The tension in the horizontal bar connecting the two halves of the ladder

[soccergenious]

A stepladder of negligible weight is constructed where x = 1.80 m. A painter of mass 63.0 kg stands on the ladder 3.00 m from the bottom.

Assuming the floor is frictionless, find the following. (Suggestion: Treat the ladder as a single object, but also each half of the ladder separately.)
(a) the tension in the horizontal bar connecting the two halves of the ladder
N

(b) the normal forces at A and B
N (at A)
N (at B)

(c) the components of the reaction force at the single hinge C that the left half of the ladder exerts on the right half
N (rightward component)
N (upward component)

I do not know how to start this problem but i know that for (b) both forces should add up to 617.4

 

[Chestermiller]

If you take moments about the top hinge (for half the ladder), you can determine the tension in the center bar. Once you know that, you can get the horizontal reaction force on the top hinge.