premise: A concert is given by a six-member band—guitarist, keyboard player, percussionist, saxophonist, trumpeter, violinist. During the concert, each member performs exactly one solo. The following restrictions apply: The guitarist does not perform the fourth solo. The percussionist performs a solo at some time before the keyboard player does. The keyboard player performs a solo at some time after the violinist does and at some time before the guitarist does. The saxophonist performs a solo at some time after either the percussionist does or the trumpeter does, but not both. If the violinist performs the fourth solo, then each of the following must be true EXCEPT:
hypothesis: The trumpeter performs a solo at some time before the violinist does.