1. Calculate: $\frac{202120212019 \cdot 202120212021 \cdot 202120212023}{100010001 \cdot\left(202120212021^{2}-4\right)}$.
1. Let $x=202120212021$.

1 POINT

Then the numerical expression takes the form:

$$
\begin{aligned}
& \frac{(x-2) \cdot x \cdot (x+2)}{100010001 \cdot \left(x^{2}-4\right)}= \\
& =\frac{x \cdot \left(x^{2}-4\right)}{100010001 \cdot \left(x^{2}-4\right)} \\
& =\frac{x}{100010001}
\end{aligned}
$$

$$
1 \text { POINT }
$$

(notice that 202120212021 $=2021 \cdot 10^{8}+2021 \cdot 10^{4}+2021=2021 \cdot 100010001$ )

$=\frac{2021 \cdot 100010001}{100010001}$

$=2021$