The fraction of undergraduate students who smoke is 15% and the fraction of graduate students who smoke is 25%. One-fifth of the University students are graduate students and the rest are undergraduates. i. What is the probability that a student who smokes is a graduate student? ii. Does this probability change if we manage to reduce the number of smokers to 3% and 5% in undergrads and grads respectively? What is the value of this new probability (that a student who smokes is a graduate student)