Sulfur dioxide has a dipole moment of 1.63 D and a bond angle of 119°.

Step 1. $\text{SO}_2$. $\cos 59.5^\circ = 0.508$, so $\mu_b = \dfrac{1.63}{2 \times 0.508} = 1.61\ \text{D}$.

Step 2. $\text{OF}_2$. $\cos 51.5^\circ = 0.623$, so $\mu_b = \dfrac{0.30}{2 \times 0.623} = 0.24\ \text{D}$.

Step 3. Read it. Oxygen and fluorine are close in electronegativity, so the $\text{O-F}$ bond is only slightly polar.