$A$ point $(x, y, z)$ moves parallel to the $x$-axis. Which of the three variables $x, y, z$ remain fixed?

The point on the $X$-axis which is equidistant from $A\ (2, -5, 7)$ and $B\ (1, 3, 6)$ is . . . . . . .

If $A(1, 2, 3)$ and $B(-1, -1, -1)$ are two points,then the distance $AB$ is:

If the coordinates of points $A$ and $B$ are $(3, 4, 5)$ and $(-1, 3, -7)$ respectively,find the equation of the locus of point $P(x, y, z)$ such that $PA^2 - PB^2 + 2k^2 = 0$.

Find the distance between the following pairs of points: $(-3, 7, 2)$ and $(2, 4, -1)$.

The distance of the point $P(x, y, z)$ from the $yz$-plane is: