D$4\mathrm{.}1.$ Given the electric field

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$1$

$2$

$($

$8$

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$+$

$4$

$$

$2$

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$$

$$

$4$

$$

$2$

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$)$

V$/$m$,$ find the differential amount of work done in moving a $6-$nC charge a distance of $2$ m$,$ starting at P$(2,2,3)$ and proceeding in the direction

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$($

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$6$

$7$

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$+$

$3$

$7$

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$+$

$2$

$7$

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; $($b$)$

$6$

$7$

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$$

$3$

$7$

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$2$

$7$

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; $($c$)$

$3$

$7$

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$+$

$6$

$7$

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$.$

Ans. $($a$)149\mathrm{.}3$ fJ; $($b$)149\mathrm{.}3$ fJ; $($c$)0$