Spotted links

Each of these is a quiz question in its own right, but the answers connect to a common theme, which could be anything from plumb straightforward to bizarrely lateral

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3 What name is given to any one of various hard, durable, black varnishes used for coating wood, metal, or other surfaces? Which domesticated bird, which typically has reddish-brown, green and yellowishbrown plumage with a metallic lustre, would you associate with American Thanksgiving and also Christmas? When you use a punching machine, it punches little circular pieces out

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5 of the paper – what are these called? Formerly in the United Kingdom 20 shillings equalled a pound; what did 21 shillings equal? What is another name for porcelain, a ceramic material made by heating clay in the form of kaolin, in a kiln?