A researcher uses an anonymous survey to investigate the firearms training of American police officers. Based on the set of 56 surveys that were completed and returned, the researcher finds that these police officers spend an average of 4.1 hours each month for firearms training.
1. For this study, the set of 56 police officers who returned surveys is an example of a(n) .
Options:
A) parameter
B) statistic
C) population
D) sample

(A) Population

It is telling you the exact amount of officers so I would think it would be (A)

step by step resolutions

1) n+n+1+n+2=51

3n+3=51

3n=48

n=16

the three numbers are 16, 17 and 18.

2) x+15=4x

3x=15

x=5

radha is now 5 years old

3) the two digits are x and y.

y=3x

(10x+y)+(10y+x)=88

y=3x

11x+11y=88

y=3x

x+y=8

x+3x=8

x=2

the original number can be either 28 or 82.

4) n+(n+2)+(n+4)=48

3n+6=48

3n=42

n=14

the numbers are 14, 16 and 18.

5) y=x+3

10y+x+10x+y=143

y=x+3

11x+11y=143

y=x+3

x+y=13

x+x+3=13

2x=10

x=5

the original number can be 57 or 75.

hope this !