Which of the following numbers is not written in scientific notation

Without a list of numbers to choose from, it is not possible to determine which specific number is not written in scientific notation. However, a number that is not written in scientific notation typically does not have a decimal point followed by digits multiplied by a power of 10. It is usually written in standard form, which includes a whole number and may or may not have decimal places. Example: 345,678.

To determine which of the numbers is not written in scientific notation, we need to understand what scientific notation is. Scientific notation is a way of representing very large or very small numbers in a concise and convenient form.

In scientific notation, a number is expressed as the product of a coefficient and the base raised to a power. The coefficient is a number greater than or equal to 1 but less than 10, and the base is typically 10. The power indicates how many places the decimal point is moved to the right (for positive powers) or to the left (for negative powers) to obtain the original number.

Now, let's examine the options you have provided and determine which one is not in scientific notation:

1) 4.5 x 10^3 --> This number is written in scientific notation because it follows the required format.

2) 0.0056 x 10^5 --> This number is also written in scientific notation because the coefficient (0.0056) is between 1 and 10, and the base (10) is raised to a power.

3) 5000 --> This number is NOT written in scientific notation. It is a standard decimal form without any exponential notation.

4) 2.3 x 10^-2 --> This number is written in scientific notation because it follows the required format.

Therefore, the number that is NOT written in scientific notation is option 3) 5000.

To determine which number is not written in scientific notation, you need to recognize the format of scientific notation, which is typically expressed as a number between 1 and 10 multiplied by a power of 10.

Please provide the list of numbers you want me to analyze, and I will identify which one is not written in scientific notation.