Answer:
What is this question asking
Step-by-step explanation:
Answer:
How many people are not allergic to any of the three choices? 22
How many people are allergic to all three choices? 1
How many people are allergic to both dogs and cats but not allergic to pollen? 7
How many people are allergic to cats only? 18
There are no real solutions
I'm taking a wild guess on what the first expression is:

First, some factoring in the denominators:


Find the common denominator:

Combine the numerators:

Expand the numerator:

Combine like terms:
Radius is half the diameter. The thickness is not used in finding this answer.
6*0.5=3
Radius is 3cm