Answer
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The writer of Morris worm was Robert Tappan Morris.
It was first released on 2nd November 1988.
It spread through the devices connected to ARPANET.
It caused the DoS (denial of service attack) on approximately 10% of total 60000 machines.
Robert Tappan Morris was sentenced to 3 years in prison, a fine 10050 USD and 400 hours of community service.