Answer:
10. 435, 11. 5.3, 12. 34.3
Explanation:
Number 10:
Since these "||" are called Absolute Value, any negative numbers would convert to a positive number. Like how -435 is inside of the Absolute Value, you would convert -435 into 435.
Number 11:
Same thing as number 10. Since -5.3 is inside of the Absolute Value, you could covert -5.3 to 5.3.
Number 12:
Since 34.3 is already a positive number inside of the absolute value, you don't need to change the sign. Only negative signs in those lines needs to change into a positive.