1) Is there any negative marking
No
2) What is the validity of the Certification.
Forever for the certification version in question
3) what will happen if the question unanswered.
You get a 0 for that question
4) In how many days after the exam I will receive the Certification.
Depends. Give it 2-6 weeks
5) Which is the best book for preparation.
SCJP study guide by Kathy and Bert
Complemented by (optionally)
SCJP sample questions by Kathy and Bert
Head first
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