Why don't all German wine labels us the same terminology? $($CH$.13)$

What kind of German wine is "sekt"? $($CH$.13)$

What is the difference between a wine designated as vino de la tierra and a wine designated as vino de la mesa? $($CH$.14)$

Why is the Rioja wine$-$producing region of Spain famous? $($CH$.14)$

How is sherry aged with the solera system? $($CH$.14)$

What does a consumer know when "AVA" is displayed on the label of a wine from the United States? $($CH$.15)$

What is the alcohol content by volume permitted on wines from the United States? $($CH$.15)$

Why are wines from the United States labeled with "Contains Sulfites"? $($CH$.15)$

What is the main wine$-$growing region of Argentina? $($CH$.16)$

What country produces Commandaria? Retsina? Tokaji Aszu? Cotnari? $($CH$.16)$