A child with a weight of $420\,\text{N}$ is seated on a swing, with her feet touching the ground. The child has an upward force from the ground of $130\,\text{N}$ and an upward force from the swing of $290\,\text{N}$. Determine the resultant force acting on the child.
- A$0\,\text{N}$
- B$260\,\text{N}$
- C$580\,\text{N}$
- D$840\,\text{N}$