Q.

Let the lines L1:r=i^+2j^+3k^+λ(2i^+3j^+4k^), λ and L2:r=(4i^+j^)+μ(5i^+2j^+k^), μ, intersect at the point R. Let P and Q be the points lying on lines L1 and L2 respectively, such that |PR|=29 and |PQ|=473. If the point P lies in the first octant, then 27(QR)2 is equal to           [2026]

1 320  
2 340  
3 360  
4 348  

Ans.

(3)