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Let $\vec{\text{F}}$ be a force acting on a particle having position vector $\vec{\text{r}}.$ Let $\vec{\tau}$ be the torque of this force about the origin, then:

1. $\vec{\text{r}}.\vec{\text{F}}=0$ and $\vec{\text{F}}.\vec{\tau}=0$
2. $\vec{\text{r}}.\vec{\tau}=0$ but $\vec{\text{F}}.\vec{\tau}\neq0$
3. $\vec{\text{r}}.\vec{\tau}\neq0$ but $\vec{\text{F}}.\vec{\tau}=0$
4. $\vec{\text{r}}.\vec{\tau}\neq0$ and $\vec{\text{F}}.\vec{\tau}\neq0$