To multiply the numbers in scientific notation, you multiply the coefficients and then add the exponents.
Given:
\[ (1.25 \times 10^3) \cdot (3.2 \times 10^2) \]
First, multiply the coefficients:
\[ 1.25 \cdot 3.2 = 4.0 \]
Next, add the exponents:
\[ 10^3 \cdot 10^2 = 10^{3+2} = 10^5 \]
Now, combine the results:
\[ 4.0 \times 10^5 \]
In scientific notation, this is:
\[ 4 \times 10^5 \]
So, the correct response is:
4×10⁵ (4 times 10 to the 5th power).