 Complete the following phrase:  Markgraf and Kronprinz both completed their trials in January 1915, after which they joined their sisters in III Battle Squadron. They took part in a series of sweeps into the North Sea that failed to locate British forces through 1915, by which time Ingenohl had been replaced by Admiral Hugo von Pohl. They also supported mine-laying operations in the North Sea and periodically rotated through the Baltic for periods of training. These operations continued into early 1916, when Pohl was in turn replaced by Reinhard Scheer. The ships again provided cover for I Scouting Group when it 