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Answer with Step-by-step explanation:
We are given a variable b
We have to state the additive property of zero using the variable b.
Additive property of zero: It states that when any number b is added to zero then we get sum is equal to number itself.
Mathematical representation:

Suppose, a number b=9
Then, 9+0=9
0+9=9
This property is called additive property of zero because when 9 is added to 0 then we get sum equals to 9.
84 cm because you HAVE to add them together.
Answer:
12.5
Step-by-step explanation: