A 770 N student stands in the middle of a frozen pond having a radius of 6.3 m. He is unable to get to the other side because of a lack of friction between his shoes and the ice. To overcome this diffuculty, he throws his 2.6 kg physics textbook horizontally toward the north shore at a speed of 6.7 m/s. The acceleration of gravity is 9.81 m/s^2 How long does it take him to reach the south shore?