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What are the geographical boundaries of the pronunciation of 鈥渦s鈥� as 鈥渦z鈥� in British English, and what is the history of it?

Danielle Jacobs,

Heemstede, The Netherlands

Is the volume of gas at the top of a beer bottle the same for all beers, and how is it optimised?

Stan Stancliffe,

Calgary, Canada

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