Physics Problem involving a cannon?

A shell is fired from a gun with a muzzle velocity of 35 m/s, at an angle of 60� with the horizontal. At the top of the trajectory, the shell explodes into two fragments of equal m (see the figure). One fragment, whose speed immediately after the explosion is zero, falls vertically. How far from the gun does the other fragment land, uming that the terrain is level and that the air drag is negligible?