You are job-shadowing a nurse in the emergency room of a local hospital. An orderly wheels in a patient who has been in a very serious accident and has had severe bleeding. The nurse quickly explains to you that in a case like this, the patient’s bed will be tilted with the head downward to make sure the brain gets enough blood. She tells you that, for most patients, the largest angle that the bed can be tilted without the patient beginning to slide off is 45.0° from the horizontal. a. On what factor or factors does this angle of tilting depend?

b. Find the coefficient of static friction between a typical patient and the bed’s sheets.