If $A=(1, 2, 3)$,$B=(3, 4, 7)$,and $C=(-3, -2, -5)$ are three points,then the ratio in which the point $C$ divides $AB$ externally is

Find the coordinates of the centroid of the triangle whose vertices are $(x_{1}, y_{1}, z_{1}), (x_{2}, y_{2}, z_{2})$ and $(x_{3}, y_{3}, z_{3})$.

If $m:n$ is the ratio in which the point $\left(\frac{8}{5}, -\frac{1}{5}, \frac{8}{5}\right)$ divides the line segment joining the points $(2, p, 2)$ and $(p, -2, p)$, where $p$ is an integer, then $\frac{3m+n}{3n} =$

Let $P(\alpha, 4, 7)$ and $Q(3, \beta, 8)$ be two points. If the $YZ$-plane divides the line segment joining $P$ and $Q$ in the ratio $2:3$ and the $ZX$-plane divides the line segment joining $P$ and $Q$ in the ratio $4:5$,then the length of the line segment $PQ$ is:

If $Q(\alpha, \beta, \gamma)$ is the harmonic conjugate of the point $P(0, -7, 1)$ with respect to the line segment joining the points $A(2, -5, 3)$ and $B(-1, -8, 0)$,then $\alpha - \beta + \gamma =$

$A$ point $R$ with $x$-coordinate $4$ lies on the line segment joining the points $P(2, -3, 4)$ and $Q(8, 0, 10)$. Find the coordinates of the point $R$.