same question no need ask so many times lah....
if u look into the older posts u'll find your answer.
anyway the answer is no, there is no such thing, even if you heard
from instructor, it is false.
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vroom...
pissssssssh...
chik chik...
vrooooooooooooooooooooooom
tingtingtingtingtingtingtingtingtingtingtingtingtingting