\begin{problem*}{23.17}
A point charge $+2Q$ is at the origin and a point charge $-Q$ is
-located along the $x$ axis at $x=d$ as in Figure P23.17. Find a
+located along the $x$ axis at $x=d$ as in Figure~P23.17. Find a
symbolic expression for the net force on a third point charge $+Q$
located along the $y$ axis at $y=d$.
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