  The notions of length of a vector field and cosine of the angle between two
vector fields over a differentiable manifold with contravariant and covariant
affine connections and metrics are introduced and considered. The change of the
length of a vector field and of the angle between two vector fields along a
contravariant vector field are found. The introduced notions are necessary for
investigations of different types of transports over a manifold of the above
mentioned type.
