Multiply. Give final answer in scientific notation.
\[
\left(5.50000000 \times 10^{1}\right) \cdot\left(8.90000000 \times 10^{-4}\right)=
\]
$\mathrm{X} 10^{\wedge}$

Step 1 ：Given the two numbers in scientific notation are \(5.5 \times 10^{1}\) and \(8.9 \times 10^{-4}\).

Step 2 ：The multiplication of two numbers in scientific notation can be done by multiplying the coefficients and adding the exponents.

Step 3 ：The coefficients are 5.5 and 8.9, and the exponents are 1 and -4.

Step 4 ：The multiplication of the coefficients gives 48.95 and the addition of the exponents gives -3.

Step 5 ：However, in scientific notation, the coefficient should be a number between 1 and 10. Therefore, we need to adjust the coefficient and the exponent to fit this format.

Step 6 ：After adjusting, the final coefficient is 4.895 and the final exponent is -2.

Step 7 ：Thus, the final answer in scientific notation is \(\boxed{4.895 \times 10^{-2}}\).