A task for bombers is the sixth level of the Fun difficulty in Lemmings. As one of several introductory levels, its intention is to familiarize the player with the various skills in the game. In this level's case, Bombing.
In the DOS version of lemmings and other subsequent ports, this level's name was changed to A task for blockers and bombers and the player was given an additional 5 blockers. This is most likely done because the original version was a bit too hard for the Fun difficulty. The original is only persent on Amiga and some early Macintosh ports.
Bomb one of the Lemmings to reach the floor below. Afterwards, turn the first lemming that walks right up to the wall separating you from the exit into a Blocker and blow it up.
If you're playing the original version you must time the lemming precisely so that he blows up next to the wall. This makes the level very similar to Diet Lemmingaid, though you are given a few more chances.