Electrostatic potential caused by two point charges

What is the difference in electrostatic potential $\varphi(\vec{r}_A) - \varphi(\vec{r}_B)$ between positions $\vec{r}_A$ and $\vec{r}_B$,

,

caused by two point charges $q_1$ and $q_2$?

Point charge $q_1=$  × 10-12 [C] is located at

 [μm],

and point charge $q_2=$  × 10-11 [C] is located at

 [μm].

What is the difference in electrostatic potential?

$\varphi(\vec{r}_A) - \varphi(\vec{r}_B) = $ [V] 

Physical constants