For a jar to be opened, a minimum torque of $20\,\text{N m}$ has to be exerted on its lid. The lid has a radius of $4.0\,\text{cm}$. What minimum force $F$ must be applied on each side of the lid so that it opens?
- A$2.5\,\text{N}$
- B$5.0\,\text{N}$
- C$250\,\text{N}$
- D$500\,\text{N}$