Work done by a constant force is given by $W=\mathrm{Force}\left(\overrightarrow{F}\right)·\mathrm{Displacement}\left(\overrightarrow{r}\right)$, where, $\overrightarrow{r}={\overrightarrow{r}}_2-{\overrightarrow{r}}_1$

Given here, $\overrightarrow{r_1}=5\hat{i}-2\hat{j}+\hat{k}$ and ${\overrightarrow{r}}_2=2\hat{i}+3\hat{j}-4\hat{k}$

So, $W=\overrightarrow{F}·\left({\overrightarrow{r}}_2-{\overrightarrow{r}}_1\right)$

$=(5\hat{i}+2\hat{j}+7\hat{k})·\left[(5\hat{i}-2\hat{j}+\hat{k})-(2\hat{i}+3\hat{j}-4\hat{k})\right]$

$\Rightarrow W=40 \mathrm{J}$