A study has shown that a male zebra finch is less likely to court a female zebra finch if he did not form any social friendships with female zebra finches when younger.

It took eleven years to built the Taj Mahal, (1632-1643).

U.S. bills are 2.61 inches wide, 6.14 inches long, and are .0043 inches thick and weigh 1 gram.

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