Answer:
6.48×10⁻⁹
Explanation:
You want the number 64.8×10⁻¹⁰ written correctly in scientific notation.
Scientific notation
A number in scientific notation has 1 digit to the left of the decimal point. The coefficient of the number shown needs to be divided by 10, and the exponent adjusted upward by 1 so the value stays the same. The result is ...
6.48×10⁻⁹
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Additional comment
A calculator or spreadsheet can display a number in scientific notation for you .
The second attachment names the parts of the number. The "coefficient" is sometimes called the "mantissa."