1. The problem asks to express the number 8 040 500 in scientific notation, which is in the form $a \times 10^n$ where $a$ is a number between 1 and 10, and $n$ is an integer. 2. To find $a$, place the decimal point after the first non-zero digit in 8 040 500. The first non-zero digit is 8, so placing the decimal point after it gives $8.040500$. 3. Now, count how many places the decimal point has moved from its original position (at the end of the number) to after the 8. The original number is 8,040,500 which can be written as $8040500.0$. 4. The decimal point moves 6 places to the left to be after the 8. 5. Therefore, $a = 8.0405$ (dropping trailing zeros is acceptable) and $n = 6$. 6. The scientific notation is: $$8.0405 \times 10^6$$ This means the number 8 040 500 is written as $8.0405 \times 10^6$ in scientific notation.