Two Point Charges Of $+ 2.00 \mu \mathrm { C }$

Two point charges of $+ 2.00 \mu \mathrm { C }$ and $+ 4.00 \mu \mathrm { C }$ are at the origin and at the point $x = 0.000 \mathrm {~m} , y =$ $- 0.300 \mathrm {~m}$ , as shown in the figure. What is the electric potential due to these charges, relative to infinity, at the point $\mathrm { P }$ at $x = 0.400 \mathrm {~m}$ on the $x$ -axis? $\left( k = 1 / 4 \pi \varepsilon _ { 0 } = 8.99 \times 10 ^ { 9 } \mathrm {~N} \cdot \mathrm { m } ^ { 2 } / \mathrm { C } ^ { 2 } \right)$

A) $117 \mathrm { kV }$
B) $36.0 \mathrm { kV }$
C) $15.7 \mathrm { kV }$
D) $56.0 \mathrm { kV }$
E) $11.7 \mathrm { kV }$