Choose the letter of the best description of the nature of light: a. light always behaves like waves. b. light always behaves like particles. c. light sometimes behaves like waves and at other times like particles. d. light never behaves like either waves or particles.

Awoman holds a book by placing it between her hands such that she presses at right angles to the front and back covers. the book has a mass of m = 1.8 kg and the coefficient of static friction between her hand and the book is μs = 0.67. no attempt 50% part (a) what is the weight of the book, fgb in newtons?