Which of the following is a identity?

Collin did the work to see if 10 is a solution to the equation r/4=2.4

Traffic on saturday, it took ms. torres 24 minutes to drive 20 miles from her home to her office. during friday's rush hour, it took 75 minutes to drive the same distance. a. what was ms. torres's average speed in miles per hour on saturday? b. what was her average speed in miles per hour on friday?

Pleas ! i just cant seem to get it right! choose: congruent or proportional choose: cf or ce or bc choose: segment addition postulate or cpctc