well nadian, i am not a science student so i have no idea regarding your question but i m very sure that you will find the answer very soon as many respectable members will try their best to satisfy you by their authentic answers.
the reference is
ENCYCLOPAEDIA OF GENERAL KNOWLEDGE. BY MUHAMMAD SUHAIL BHATTI

THANKS ONCE AGAIN MAM and sulershi for being so supportive.
regards

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''A man is not finished if he is defeated, he is finished if he quits.''