Let D equal the set of countries who have won more than 250 Silver medals. Write the set D using the roster method. Let the universal set consist of the 10 countries listed in the table. Use the country abbreviations US, SU, GB, G, F, I, S, C, R, and EG when writing the set.

Mahnoor randomly selects times to walk into a local restaurant and observe the type of music being played she found that the restaurant was playing country 11 times rock & roll 17 times and blues 8 times use the observed frequencies to create a probability model for the type of music the restaurant is playing the next time mahnoor walks in.