If $\overrightarrow A = 2\hat i + 4\hat j - 5\hat k$,the direction cosines of the vector $\overrightarrow A$ are:

  • A
    $\frac{2}{\sqrt{45}}, \frac{4}{\sqrt{45}}, \text{and } \frac{-5}{\sqrt{45}}$
  • B
    $\frac{1}{\sqrt{45}}, \frac{2}{\sqrt{45}}, \text{and } \frac{3}{\sqrt{45}}$
  • C
    $\frac{4}{\sqrt{45}}, 0, \text{and } \frac{4}{\sqrt{45}}$
  • D
    $\frac{3}{\sqrt{45}}, \frac{2}{\sqrt{45}}, \text{and } \frac{5}{\sqrt{45}}$

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