These waves travel at the speed of sound, but when a jet travels at Mach 1 and above these waves merge into one single shock wave as they cannot get out of the way of each other quickly enough.

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One problem with a single currency is that an external shock can hit some countries or regions harder than others.

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Conditions can be quite a shock for those used to warm, single rooms, televisions and games consoles.

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And the single biggest reason for this lamentable and potentially calamitous culture shock is that so many of our potential leaders are coming of age in fatherless homes.

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"It's getting back into getting up at six in the morning and getting down to the lake and it's going to be a shock to the body having to do it every single day for the next few months, " he added.

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