how would you write 0.0005 in scientific notation? 50×10^5 5×10^(-4) 5×10^(-3) 5×10^3

Explanation:

Step1: Recall scientific - notation form

Scientific notation is $a\times10^{n}$, where $1\leq|a|\lt10$ and $n$ is an integer.

Step2: Move the decimal point

For the number $0.0005$, move the decimal point 4 places to the right to get a number between 1 and 10. So $a = 5$.

Step3: Determine the exponent

Since we moved the decimal point 4 places to the right, $n=-4$. So $0.0005 = 5\times10^{-4}$.

Answer:

B. $5\times 10^{-4}$