Show that the points `A(1, -2, -8), B(5, 0, -2) and C(11, 3, 7)` are collinear, and find the ratio in which B divides AC.

Explanation

To show that the points A(1, -2, -8), B(5, 0, -2), and C(11, 3, 7) are collinear, we will follow these steps:

### Step 1: Find the vectors AB, BC, and AC
1. **Vector AB**:
\[ \vec{AB} = \vec{B} - \vec{A} = (5 - 1, 0 - (-2), -2 - (-8)) = (4, 2, 6) \]

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