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Let k ˆ 5 j ˆ 3 i ˆ 4      and k ˆ 4 j ˆ 2 i ˆ      . Let 1   b e parallel to   and 2   be perpendicular to   . If   = 1   + 2   , then the value of 2 5   . ) k ˆ j ˆ i ˆ (   is

1. 7
2. 9
3. 6
4. 11

Correct answer: 7

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