## Task B-3.2.

Let $A=1202^{2}+2^{2021}$. Determine the units digit of the number $A^{2021}$.
## Solution.

The unit digit of the square of the number 1202 is 4.

1 point

Powers with a base of 2 have unit digits in the sequence $2,4,8$, 6, depending on the remainder when the exponent is divided by 4.

Therefore, the unit digit of the number $2^{2021}$ is 2.

Then the unit digit of the number $A$ is $4+2=6$.

The unit digit of any power with a base of 6 is always the number 6.

Therefore, the unit digit of the number $A^{2021}$ is also 6.

1 point