document.write( "Question 413523: Four-Digit Number. How many four-digit numbers can be formed using the digits 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 if the first digit cannot be 0? Repeated digits are allowed.\r
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Algebra.Com's Answer #581207 by jilalbenkad(2)\"\" \"About 
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9*(10)^3= 9000 \n" ); document.write( "
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