**Find the angle between the vectors. (First find an exact expression and then approximate to the nearest degree.)**

**a = 4i - 3j + k, b = 2i - k**

**Answer:**

**Find the angle between the vectors. (First find an exact expression and then approximate to the nearest degree.)**

**a = 4i - 3j + k, b = 2i - k**

**Answer:**