Given u = ⟨3, 2⟩, v = ⟨1, 5⟩, and the angle between the vectors is 45°, what is u · v?

For vectors u = ⟨3, 2⟩ and v = ⟨1, 5⟩, multiply corresponding components and add: u · v = (3)(1) + (2)(5) = 3 + 10 = 13. This matches choice C, 13.

AI-written and checked against the verified answer.