1. The problem asks to represent each given number in standard form, which means expressing the number as a product of a number between 1 and 10 and a power of 10. 2. The general formula for standard form is: $$a \times 10^n$$ where $1 \leq a < 10$ and $n$ is an integer. 3. Let's convert each number: - $349007.9 = 3.490079 \times 10^5$ - $684237.4 = 6.842374 \times 10^5$ - $378008.8 = 3.780088 \times 10^5$ - $837407.3 = 8.374073 \times 10^5$ - $457380.9 = 4.573809 \times 10^5$ - $307988.8 = 3.079888 \times 10^5$ - $290538.6 = 2.905386 \times 10^5$ 4. Each number is rewritten so that the decimal point is after the first digit, and the exponent $n$ counts how many places the decimal point moved to the left. Final answers: - $349007.9 = 3.490079 \times 10^5$ - $684237.4 = 6.842374 \times 10^5$ - $378008.8 = 3.780088 \times 10^5$ - $837407.3 = 8.374073 \times 10^5$ - $457380.9 = 4.573809 \times 10^5$ - $307988.8 = 3.079888 \times 10^5$ - $290538.6 = 2.905386 \times 10^5$