Answer:
1. Rags to riches
This is an example of rags to riches because the place started as a humble enterprise ("a poor, struggling, little hand-to-mouth enterprise") and ended up becoming a successful one ("celebrated, and overcrowded with customers").
2. Rags to riches
This is also an example of rags to riches because the initial situation of the character was humble ("clerking away... on a salary"), but he became successful in the end ("a vast millionaire, and a colossal celebrity").
3. Impending doom
This passage demonstrates impending doom because it states that the crash is coming, and that total destruction might follow.
4. Wealth worship
The passage shows wealth worship because the plain clothes are being thrown in the fire and the fancy ones are being praised.
5. Impending doom
The passage refers to impending doom because the man is deep in debt, compromised and with no promise of a salary.