For this case we have the following expression:
![843,219](https://img.qammunity.org/2020/formulas/mathematics/middle-school/llf17aj63jaudm4rnefx606zxd8mulhz8l.png)
When multiplying to the power of 100 we have:
![843,219 * 100 = 843,219 * 10 ^ 2 = 84,321,900](https://img.qammunity.org/2020/formulas/mathematics/middle-school/rwmzbdot80dgq2mwlxns7mcqqv6cocxv1b.png)
We have to:
0: Unit
0: Ten
9: Hundred
1: One thousand unit
2: Ten thousand
3: One hundred thousand
4: Million unit
8: Ten million
Thus, the unit digit is 0.
Answer:
0