1. What are the concerns of project manager Bryan Lee? he is concerned "Do building methods and materials match those in the agreement? Are schedlues met?". "Are costs kept within bounds?".

2. Why do they engineers and construction workers use a boring machine to make tunnels instead of cut and cover construction? It will be lowered piece by piece and assembled on the excavation's floor.

3. What do the worker’s do to protect themselves in the newly formed tunnels from harmful levels of gases found in the soil at the various new subway sites? To protect their health, they have a built-in gas detecto, and each wears a belt equipped with an oxygen mask and a short, lifesaving supply of oxygen.