WHAT ARE YOU WAITING FOR?

# Explanation

### Explanatory Answer

If they are 2C/5 apart they have either covered C/2-2C/5 = C/10 together, then they will be 2C/5 distance apart after **4 minutes and after every 40K + 4 minutes.**

If they met and travelled 2C/5 distance away from each other, they will be 2C/5 distance apart after 20 + 16 minutes = **36 minutes or after every 40K + 36 minutes.**

If they met and travelled 3C/5 distance away from each other, they will be 2C/5 distance apart after 20 + 24 minutes = **44 minutes or after every 40K + 44 minutes.**

So, 68 is not a possible value of t.