Answer:
$4
Step-by-step explanation:
Total consumer surplus is given by the difference between the willingness to pay of each customer to the actual price of a good.
Since Avery is only willing to pay $10 and the pizza costs $12, Avery will not buy a pizza and should not be considered for consumer surplus.
Since Pia is willing to pay $13, and Sylvio is willing to pay $15, consumer surplus is:

When the price of pizza is $12, a consumer surplus of $4 is achieved.
I believe it’s B. The others didn’t seem correct.
Answer:
18
Step-by-step explanation:
The diameter is equal to twice the length of the radius
So if the radius is 9 then the diameter is 9 * 2 = 18
Square root of 88 is 9.38083152
Square root of 95 is 9.746794345
9.38083152 + 9.746794345 = 19.12762586