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

What is the best way to answer questions with a x expression in the question. for example 3x + 10x=?

Select all of the following expressions that are equal to 2.5.

Statements reasons 1. ab ? cd; ad ? bc 1. given 2. ac ? ac 2. reflexive property 3. ? adc ? ? cba 3. ? 4. ? dac ? ? bca; ? acd ? ? cab 4. cpctc 5. ? dac and ? bca are alt. int. ? s; ? acd and ? cab are alt. int. ? s 5. definition of alternate interior angles 6. ab ? cd; ad ? bc 6. converse of the alternate interior angles theorem 7. abcd is a parallelogram 7. definition of parallelogram what is the missing reason in step 3?