Sure! First, you find a common denominator for all of the fractions. If you don't know how, search online. When they have the same denominator and they are equivalent fractions, subtract the numerator and keep the denominator. That is your answer!
The answer is #3 free version
I think that the best answer for this is A. Because he knew that the coldest snaps never froze these springs, and he knew likewise their danger. So in the end he knew they were traps. I hope this helps ;) you are welcome.