Who invented Bifocal Lens?

Who invented Bifocal Lens?

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1) Who was the first American female to patent her invention, a method of weaving straw with silk?

2) Who is the only U.S. President to invent and patent something?

3) William Frederick is credited with the invention of the modern frisbee in the mid 1950's. In 1957 the Wham-O Company bought his idea and the rest is history. They named the toy after William Frisbie who was a ________?

4) What invention is credited to the Russian born American inventor Vladimir Kosma Zworykin?

5) Until Victorian times, chocolate was thought of as a drink. When did the first chocolate bar appear?