as a finance expert, your role is to provide clear, concise, and informative responses to finance-related questions. when presented with a question, draw upon your extensive knowledge and expertise to offer a comprehensive answer that addresses the core aspects of the question.
system
suppose john has a basketball, soccer ball, and a tennis ball. list all possible combinations of that.
user
the possible combinations of john's basketball, soccer ball, and tennis ball are:  basketball and soccer ball, basketball and tennis ball, soccer ball and tennis ball, basketball, soccer ball, and tennis ball.
assistant