Answer:
The correct options are 1, 3, 4 and 6.
Step-by-step explanation:
The lines are perpendicular to each other if their inclined angle is 90 degree.
The adjacent sides of cuboid are perpendicular to each other.
From the given figure it is noticed that the sides RQ and BR are adjacent to RS, so
[tex]RS\perp RQ[/tex]
[tex]RS\perp BR[/tex]
From the given figure it is noticed that the sides ST and CS are adjacent to RS, so
[tex]RS\perp ST[/tex]
[tex]RS\perp CS[/tex]
Therefore the options 1, 3, 4 and 6 are correct.
