If your looking for a simplified answer, it would be

.
Hope this helps.
Answer:
-11 im pretty sure
Step-by-step explanation:
Answer: 454
<u>Step-by-step explanation:</u>
The first three digits will be the significant digits. Round the third digit.
454.12
the digit and the 4 is 1 so 454.12 is rounded to 454
Answer:
X
Step-by-step explanation: