Subject: mathqa
Question: if the probability of rain on any given day in chicago during the summer is 20 % , independent of what happens on any other day , what is the probability of having exactly 3 rainy days from july 4 through july 7 inclusive ?
Option: 
A: 3 / 125
B: 16 / 625
C: 2 / 25
D: 7 / 125
Answer: B