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Once Edison had marketed his first successful invention-a stock ticker and printer- for $40,000.
I'm confused. Are stock ticker and printer two different machines or just one?
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You mean it's a single machine?
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Do you know how to use a search engine for research, sundarnaz?
Yes I know. I Googled this phrase or word, whateve it is, before posting it hear. It showed results about Edison and etc. I got no idea.
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sundarnaz I got no idea.
You need to try harder. I found plenty of information. That search offers about 397,000 results.
I just hit upon the idea that it probably a single machine because the word "invention" is used. If they were two machines it would be "inventions". Am I right?
That's a logical conclusion, yes!
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