Need to know the answer to this picture

If lmn=xyz, which congruences are true by cpctc? check all that apply

Afrequency table of grades has five classes (a, b, c, d, f) with frequencies of 3, 13, 14, 5, and 3 respectively. using percentages, what are the relative frequencies of the five classes?

This is about circle theorems. someone asap : (