In a pickup game of dorm shuffleboard, students crazed by final exams utilize a broom to propel a calculus book along the dorm hallway. If the 3.5 kg book is pushed from rest during a distance of 0.88 m by the horizontal 28 N force from the broom and then has a speed of 1.64 m/s, what is the coefficient of kinetic friction among the book and floor?