Final answer:
The number that has a digit 5 is 1/1000 the value of the digit 5 in 542.79 is 0.00054279 (option c).
Step-by-step explanation:
To find a number that has a digit 5 that is 1/1000 the value of the digit 5 in 542.79, we need to divide the original digit 5 value by 1000. The digit 5 in 542.79 is in the hundredth place, so dividing it by 1000 moves it three decimal places to the right. Therefore, the number we are looking for is 0.00054279 (option c). Now, you want a number where the digit 5 is 1/1000 (one thousandth) the value of the digit 5 in 542.79. To achieve this, you need to move the digit 5 three places to the right. This is because 1/1000 is equivalent to moving three places to the right in the decimal system.