Final answer:
The length of a football field expressed in scientific notation is 4.32×10³.
Step-by-step explanation:
To express the length of a football field in scientific notation, we need to convert the given length into a number between 1 and 10, multiplied by a power of 10.
The given length of the football field is 4,320 inches. To convert this value into scientific notation, we move the decimal point three places to the left and multiply by 10 raised to the power of 3, as each place of decimal shift corresponds to a power of 10.
Therefore, the value expressed in scientific notation is 4.32×103