The distance of the point $(1,2)$ from the line $x+y=0$ measured parallel to the line $3 x-y=2$ is

The circumradius of the triangle formed by the lines $x y+2 x+2 y+4=0$ and $x+y+2=0$ is

From the following options, the nearest line to the origin is ….

If the pair of straight lines $x y-x+y-1=0$ and the line $x+\mathrm{k} y-3=0$ are concurrent, then the value of $k$ is equal to