Mrs. barlow's math class took a test yesterday. out of 60 students, 70% of them passed. how many of mrs. barlow's students passed the test?

42.
60/100=.6
.6x70=42 

The first one, i believe, would be correct. all the others have one thing in common, and that's that they have repeating numbers. in the second one, x and y have repeating 6's and 3's, and in the third, x and y have repeating 6's as well. in the last one, there are repeating 3's. the first one has no repeating numbers.

The answer to your question is b’(16,14)