Of the 50 states in the Unites States, Alaska has the largest percentage of males and Rhode Island has the largest percentage of females. (Interestingly, Alaska is the largest state and Rhode Island is the smallest). According to the 2010 US Census, the population of Alaska is 52.0% male and the population of Rhode Island is 48.3% male. If we randomly sample 300 people from Alaska and 300 people from Rhode Island, what is the approximate distribution of p̂_a − p̂_ri, where p̂_a is the proportion of males in the Alaskan sample and p̂_ri is the proportion of males in the Rhode Island sample?