Answer:
C
Step-by-step explanation:
18 boys
Answer:
1120°
Step-by-step explanation:
Use the sum of interior angles formula:

Where n is the number of sides.
In a nonagon, there are 9 sides, substitute 9 for n:

Since our nonagon is a regular nonagon, all 9 angles measure the same, so each angle measures:

Subtract 140 from 1260:

I have an expression

floating around in my head; let's see if it makes sense.
The variance of binary valued random variable b that comes up 1 with probability p (so has mean p) is

That's for an individual sample. For the observed average we divide by n, and for the standard deviation we take the square root:

Plugging in the numbers,

One standard deviation of the average is almost 2% so a 27% outcome was 3/1.9 = 1.6 standard deviations from the mean, corresponding to a two sided probability of a bit bigger than 10% of happening by chance.
So this is borderline suspect; most surveys will include a two sigma margin of error, say plus or minus 4 percent here, and the results were within those bounds.
Answer: 43
Step-by-step explanation: