Only $L_2$ and $L_4$ are CFL because there is only one comparison at one time and CFL can do one comparison.
$L_2 = i \leq j \text{ or } j \leq i$. So, there is no relation between $i$ and $j$, and they can be anything. (The condition becomes trivial as any $i$ and $j$ satisfies it). Thus, we can read all the $a$'s without pushing into stack. To ensure that $j=k$, push all $b$s into stack. When we encounter $c$'s pop all $b$'s one by one. Thus, it is a DCFL.
$L_4$: $i=j$ can be checked by pushing for $a$'s and popping for $b$'s. If at the end of popping for $b$'s, we end up with an empty stack, we need to check that $c$'s are even, which can be accomplished by a D-PDA. If we end up on a non-empty stack, we accept. Thus, $L_4$ is also a DCFL.
