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Choose the correct answer.

The diameter of a white blood cell is [tex]0.000591[/tex] in. Which of the following is this number written in scientific notation?

A. [tex]0.591 \times 10^{-3}[/tex] in
B. [tex]5.91 \times 10^{-4}[/tex] in
C. [tex]591 \times 10^{-6}[/tex] in
D. [tex]59.1 \times 10^{-5}[/tex] in

Answer :

Sure! Let's work through the problem step-by-step to write the diameter of the white blood cell in scientific notation.

1. Understand the decimal number:
The number given is [tex]\(0.000591\)[/tex] inches.

2. Identify the significant figures:
This number has three significant figures: 5, 9, and 1.

3. Place the decimal point:
We need to express this number in the form of [tex]\(a \times 10^b\)[/tex], where [tex]\(1 \leq a < 10\)[/tex].

4. Move the decimal point:
To convert [tex]\(0.000591\)[/tex] to a number between 1 and 10, we need to move the decimal point 4 places to the right:
[tex]\[
5.91
\][/tex]
So, [tex]\(0.000591\)[/tex] can be written as [tex]\(5.91 \times 10^{-4}\)[/tex].

Therefore, the correct scientific notation for the diameter of the white blood cell is:
[tex]\[ \boxed{5.91 \times 10^{-4}} \][/tex]

Among the given choices:
1. [tex]\(0.591 \times 10^{-3}\)[/tex] in
2. [tex]\(5.91 \times 10^{-4}\)[/tex] in
3. [tex]\(591 \times 10^{-6}\)[/tex] in
4. [tex]\(59.1 \times 10^{-5}\)[/tex] in

The correct answer is [tex]\(5.91 \times 10^{-4}\)[/tex].

So, the answer is:
[tex]\[ \boxed{2} \][/tex]