A cross-shaped arrangement, pivoted freely at O, has arms measuring $5.0\ \text{m}$, $4.0\ \text{m}$, $3.0\ \text{m}$ and $2.0\ \text{m}$. Forces of $2.0\ \text{N}$, $3.0\ \text{N}$, $4.0\ \text{N}$ and an unknown force $F$ act on it. The arrangement is in rotational equilibrium. What is the magnitude of force $F$?
- A$0.40\ \text{N}$
- B$2.0\ \text{N}$
- C$2.6\ \text{N}$
- D$4.4\ \text{N}$