In a recent paper of Buckmaster and Vicol, ArXiv:1709.100033v2 the authors develop a constructions of weak solutions of the Navier-Stokes equations with an arbitrary energy profile. This result builds on previous papers by the first author, De Lellis, Isett and Szekeldyhiki on nonuniqueness of solutions for the Euler equation. A basic tool in their approach is the use of Bernoulli flow, classical steady solution of the Euler equations, to construct highly oscillatory approximate solutions to these equations. A particular emphasis will be placed on the construction and properties of these solutions. This is a continuation of the lecture from Feb 25, 2018.