2. Let s, t be distinct vertices of a digraph G, and let c : E(G) → Z+.

Let φ be a c-admissible s − t ﬂow of value k and suppose there is a

c-admissible ﬂow with value > k. Does it follow that there is a c-

admissible ﬂow ψ of value > k so that φ(e) ≤ ψ(e) for every edge

e?

Let φ be a c-admissible s − t ﬂow of value k and suppose there is a

c-admissible ﬂow with value > k. Does it follow that there is a c-

admissible ﬂow ψ of value > k so that φ(e) ≤ ψ(e) for every edge

e?