What is the value of x given the fact that under the same conditions of temperature and pressure, methane (CH4) effuses 3.3 times faster

I’m not sure about this question

You can look it up online and some images should pop up 

Well you can immediately rule out a and d because if a metal were to lose or gain protons, then it would become a different element all together. the answer here is b because the positive symbol with a number refers to how many electrons the metal can give away to become stable.