To examine the relationship between categories use a
a. two-way frequency table
ob. calculation table
oc. conditioner table
od. table of values

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 would be 13.5 minutes.

The following relation is not a function