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# If the position vector of $A,B$ and $C$ are respectively $2 \bar i - \bar j +\bar k, \bar i - 3 \bar j - 5 \bar k$ and $3 \bar i - 4 \bar j - 4 \bar k$, then $\cos ^2 A=$

$\begin {array} {1 1} (1)\;0 & \quad (2)\;\frac{6}{41} \\ (3)\;\frac{35}{41} & \quad (4)\;1 \end {array}$

$(3) \; \frac{35}{41}$