Encyclopedia britannica's list of 20 world class orchestras include the following from the united states: boston symphony orchestra, cleveland orchestra, chicago symphony orchestra, los angeles philharmonic, new york philharmonic, philadelphia orchestra, and the san francisco symphony. choose 5 at random from the list of 20 for a benefit cd.
what is the probability that the collection will include at least one group from the united states?
at least 2 from the united states?
that all 5 will be from the united states?

it's a question with 3 different parts. explain how you did it. : )