A surveyor measured the distance between two points on the plan drawn to a scale of $1 \mathrm{~cm}=40 \mathrm{~m}$ and the result was 468 m . Later, it was discovered that the scale used was $1 \mathrm{~cm}=20 \mathrm{~m}$.

The true distance between the points (in m ) is __________ (round off to the nearest integer).

If the Fore Bearing of the lines AB and BC are $60^{\circ}$ and $122^{\circ}$, respectively, then the interior angle $\angle A B C$ (in degrees) is ________ (round off to the nearest integer).

The most suitable test for measuring the permeability of clayey soils in the laboratory is ___________