Which of the following is the additive identity of 5+21

The answer is D

Step-by-step explanation:

Additive Identity is an identity element (such as 0 in the group of whole numbers under the operation of addition) that in a given mathematical system leaves unchanged any element to which it is added.

For example: 2 + 0 = 2. 0 + 5 = 5.

So, therefore the answer is 0

Hope this is helps and you undertand this :)

marco saved more.   he saved $35 more.

step-by-step explanation:

1+2+3+4+5+6+7+8+9+10 = 55

2*10 = 20

55-20 = 35

she was supposed to add the hours(38.5) and multiply the amount of money she earned(7.50) resulting in $288.75 .

correct me if i'm wrong and if it is i'm truly sorry.