What are u asking? u gave no question or picture
Answer:

Step-by-step explanation:
Step 1: Expand by distributing sum groups.

Step 2: Expand by distributing terms.

Step 3: Expand by distributing terms.

Step 4: Collect like terms.

Step 5: Simplify.

If you're referring to the different sets of real numbers, it's the ones that you could try to do subtraction and not get an answer that still in that set.
For example, natural numbers (aka 1, 2, 3, 4, ...) are not, because 7 - 11 = -4 and -4 is not a natural number.
Also, whole numbers (aka 0, 1, 2, 3, 4, ...) has the same issue.
Basically any set of real numbers that doesn't include negative numbers will have this issue.
D 200 minutes
.15*200 = 30+45= Plan A= $75
.25*200= 50+25= Plan B= $75
Answer is D
This is already written with positive exponent