How many times faster does a supersonic submarine travel than a commercial airliner?
Which is not a problem facing the supersonic submarine technology?
(1) Sufficient initial speed to generate supercavitation
(2) Waterproof submarine shell at a supercavitation speed
(3) Change of direction at supercavitation regime
How old do infants usually start to laugh?
Send your name and answers (both Brain Builders and Mission of the Month) with JPC membership number and district to: PPRB, 11/F Arsenal House, Police Headquarters, 1 Arsenal Street, Wan Chai, or to any district JPC Clubhouse no later than 18 December 2014.
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