2. The number 11 can be represented as the sum of four squares of numbers in only one way, disregarding the order of the addends:

$$
11=9+1+1+0=3^{2}+1^{2}+1^{2}+0^{2}
$$

Can the number 99 be represented as the sum of four squares in two different ways?
Answer. Yes, it can be done. There are even more than two ways:

$$
\begin{gathered}
99=7^{2}+7^{2}+1^{2}+0^{2}=7^{2}+5^{2}+5^{2}+0^{2}=8^{2}+5^{2}+3^{2}+1^{2}=9^{2}+4^{2}+1^{2}+1^{2}= \\
=9^{2}+3^{2}+3^{2}+0^{2} .
\end{gathered}
$$

## Grading Criteria.

- Correct answer (two or more ways are provided), explanations are not required - 7 points.
- Only one decomposition into the sum of four squares is provided (regardless of the answer - "yes" or "no") - 3 points.
- Only the answer "yes, it can be done" - 0 points.