Both +33 and -33 are units of zero because both start from 0.
<h3>Explanation:-</h3>
This is because, -33 starts from the left side of zero, whereas, +33 starts after some numbers in zero. Either left or right, as they both have a common number 0, therefore, <u>-</u><u>3</u><u>3</u><u> </u><u>and </u><u>+</u><u>3</u><u>3</u><u> </u><u>are </u><u>units</u><u> of</u><u> zero</u><u>.</u>