Kami booked a vacation to Europe. She booked the trip with a travel agent on March 10, 2020 and the trip was to be July 15-25 2021. With the resulting pandemic, state lockdowns, and travel bans for Americans to EU countries, on July 1, 2020 Kami wishes to have her travel contract discharged and get her payment back. The agent argues that the cause of these events: COVID-19, was first reported in the US on January 21, 2020, which was before Kami booked her trip. Which of the discharge methods, if any, would help Kami and why is that method her best argument?