Find the line integrals of $\mathbf{F}$ from $(0,0,0)$ to $(1,1,1)$ over each of the following paths in the accompanying figure.
a. The straight-line path $C_1: \mathbf{r}(t)=t \mathbf{i}+t \mathbf{j}+t \mathbf{k}, \quad 0 \leq t \leq 1$
b. The curved path $C_2: \mathbf{r}(t)=t \mathbf{i}+t^2 \mathbf{j}+t^4 \mathbf{k}, \quad 0 \leq t \leq 1$
c. The path $C_3 \cup C_4$ consisting of the line segment from $(0,0,0)$ to $(1,1,0)$ followed by the segment from $(1,1,0)$ to $(1,1,1)$
Figure can't copy
$\mathbf{F}=x y \mathbf{i}+y z \mathbf{j}+x z \mathbf{k}$