Which of the following best describes the location of the Fertile Crescent? a.

The Fertile Crescent begins at the Persian Gulf and continues northwest to the Mediterranean Sea.

c.

The Fertile Crescent is in both Europe and Asia and is about the size of Russia.

b.

The Fertile Crescent includes both the Tigris and Euphrates rivers.

d.

Both A and B

Select the best answer from the choices provided

A
B
C

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.