A rod that is uniform and $200\ \text{cm}$ long is pivoted freely at point $P$. It remains horizontal in equilibrium because a $60\ \text{N}$ weight is connected to the rod by a string that runs over a frictionless pulley. Determine the weight of the rod.
- A$30\ \text{N}$
- B$60\ \text{N}$
- C$80\ \text{N}$
- D$140\ \text{N}$