Derf cried out to the others. It was a cry of victory. “The Tobors are only machines! They aren’t gods at all! They are only machines! They can be broken!” The cry went round the city. The Nems stopped work, and attacked the Tobors.Now there was no danger from the Tobors. Their power had gone. Soon, the city belonged to the Nems. Derf was the hero of the city. Derf stood in front of the giant computer at The Centre.It was running down, now. But a few lights were still on and some sounds came from it. It would answer a few questions before 5 it broke down completely. The computer’s voice was weak, and Derf had to listen very carefully to the answers.“Robots were made by men,” it said. “Robots must never kill men. Robots must …” The voice died away. There was silence. And then, Derf understood. (1) What was the greatest surprise for Derf and others ?(2) Who took over the city?(3) How was Derf the hero of the city?(4) What secret did Derf know from the computer ?(5) The meaning of ‘running down’ is…(a) ‘losing power gradually and ceasing to function’.(b) ‘developing defects’.(c) ‘losing contact’.