Trainee Engineer

On his first day trainee dialed the kitchen and shouted into the phone:"Get me a cup of coffee, quickly!"
The voice from the other side responded: "You fool; you've dialled the wrong extension!
Do you know who you're talking to?"
"No" replied the trainee.
"It's the Managing Director of the company, you idiot!
"The trainee shouted back: "And do you know who YOU are talking to, you IDIOT?"
"No!" replied the Managing Director angrily.
"Thank God!"replied the trainee and put down the phone...

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