Answer:
The diameter would be 11 feet
Step-by-step explanation:
C = pi * d
we don't know D so we rearrange the equation to solve for D by dividing both sides by pi:
C/pi = d
Now we plug in everything
11pi/pi = d
The pi cancel each other out leaving with 11 feet
Therefore D = 11 feet
The answer is 8 days.
4/5 divided 1/10
4/5 x 10/1
40/5 = 8
(-2,-5) is the answer for this by doing -6-4 and -8–2
Not addition, since

and 0 doesn't belong to the set.
Not subtraction, since

.
It is closed under multiplication. The set appears to contain all non-zero multiples of 3.
Not division, since dividing some of the numbers results in rationals which do not belong to the set.
What other operations are you supposed to consider?