If the coordinates of the points P, Q, R, S a | vedclass

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(D) The direction ratios of line $PQ$ are $(4-1, 5-2, 7-3) = (3, 3, 4)$.The direction ratios of line $RS$ are $(2-(-4), 0-3, 2-(-6)) = (6, -3, 8)$.For

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None of these

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(D) The direction ratios of line $PQ$ are $(4-1, 5-2, 7-3) = (3, 3, 4)$.The direction ratios of line $RS$ are $(2-(-4), 0-3, 2-(-6)) = (6, -3, 8)$.For $PQ \parallel RS$,the ratios of direction ratios must be equal: $\frac{3}{6} = \frac{3}{-3} = \frac{4}{8}$,which is $\frac{1}{2} = -1 = \frac{1}{2}$. This is false.For $PQ \perp RS$,the dot product of direction ratios must be zero: $(3)(6) + (3)(-3) + (4)(8) = 18 - 9 + 32 = 41 
eq 0$. This is false.For $PQ = RS$,the lengths are $PQ = \sqrt{3^2 + 3^2 + 4^2} = \sqrt{9 + 9 + 16} = \sqrt{34}$ and $RS = \sqrt{6^2 + (-3)^2 + 8^2} = \sqrt{36 + 9 + 64} = \sqrt{109}$. Since $\sqrt{34} 
eq \sqrt{109}$,this is false.Therefore,none of the given options are correct.

If the coordinates of the points $P, Q, R, S$ are $(1, 2, 3), (4, 5, 7), (-4, 3, -6)$ and $(2, 0, 2)$ respectively,then:

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