A horrifying room contains 1000 really stupid flies. This room has dimensions of 3m X 3m X 3m, and it has one open window with dimensions of 1m X 0.5m. The thickness of the window frame (the distance from the inside of the room to the outside) is 30cm. The flies buzz around with a constant speed of 2 m/s, and they fly in straight lines until they bump into each other or the wall. After the collision they fly off in a random direction. Outside the room there are essentially no flies. At what rate would you expect the flies to be exiting the room through the window? Answer will be exact.

a) 10.3 flies/s

b) 102.6 flies/s

c) 21.4 flies/s

d) 68.2 flies/s

e) 30.9 flies/s