A TURN ON THE SCREW

                      There was a industrialist whose production line inexplicably breaks down, costing him millions per day. He finally tracks down an expert who takes out a screwdriver, turns one screw, and then - as the factory cranks back to life. The expert presents a bill for Rs.10,000. 

Affronted, the factory owner demands an itemised version. The expert is happy to oblige:
For turning a screw: Rs.1, 
For knowing which screw to turn: Rs.9,999.