$-j$ for $j=-6$

Step 1 ：The question is asking for the value of $-j$ when $j=-6$.

Step 2 ：This is a simple arithmetic operation where we multiply $-1$ with the value of $j$.

Step 3 ：Substitute $j = -6$ into $-j$.

Step 4 ：So, $-j = -(-6) = 6$.

Step 5 ：Final Answer: The value of $-j$ for $j=-6$ is \(\boxed{6}\).