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Let k ˆ j ˆ i ˆ a β + α + = G , α , β, ∈ R. Let a vector b G be such that the angle between a and b G is 4 π and 2 b G = 6. If b a G G ⋅ = 2 3 , then the value of ( α 2 + β 2 ) 2 b a G G × is

1. 75
2. 85
3. 90
4. 95

Correct answer: 90

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