Problem $2.$

The two charges $q_1$ and $q_2$ shown in the figure have equal magnitudes. What is the net $($vector$)$

electric field due to these two charges at points A $($midway between the charges; the distance

between the charges is $s),$ B $($a distance $L$ upward from point A$),$ and C $($a distance $L$ downward

from point A$)$ if

$($a$)$ both charges are negative,

$($b$)$ both charges are positive,

$($c$)q_1$ is positive and $q_2$ is negative