CAN SOMEONE PLS HELP ME ANSWER BOTH OF THESE (OR JUST ONE). ILL GIVE A BRAINIEST TO WHOEVER CAN ANSWER THEM. TYSM :)

Aria drove to the store, did some shopping, and then came home. during maria's trip, when was her displacement equal to zero?

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.

Need only answer if you think you know it