Which of the following can a hospital do to reduce the spred of infectious diseases?
a. have patients wash often using antibacterial soap
b. keep infected patients confined, and limit visitors
c. serve food to patients confined in paper towels, and dispose of waste in the trash
d. do not allow cleaning personnel into room occupied by infected patients
d?

Consider a double atwood machine constructed as follows: a mass 4m is suspended from a string that passes over a massless pulley on frictionless bearings. the other end of this string supports a second similar pulley, over which passes a second string supporting a mass of 3m at one end and m at the other. using two suitable generalized coordinates, set up the lagrangian and use the lagrange equations to find the acceleration of the mass 4m when the system is released. explain why the top pulley rotates even though it carries equal weights on each side.