A computer having a memory stores instructions for receiving data. The power tool has a frame, including a handle to be grasped by the operator, an implement affixed to the frame having a rotary input member, and a small four-cycle, lightweight, internal combustion engine attached to the frame for driving the implement. A fire retardant agent is then added and the materials are ground in a finish mill. The integrator provides an output voltage to a drive electrode that electrostically controls the position of the MEMS structure. The bottlenecks are identified to resolve problems originating at a specific subsystem. The string entrained around the rolls is tensioned by retarding the string upstream from the rolls with a gas flow and by accelerating the string downstream from the rolls with a gas flow.