Answer:
Explanation: While the main idea is usually in the first sentence, the next most common placement is in the last sentence of a paragraph. The author gives supporting information first and then makes the point in the last sentence. Here's a paragraph we can use as an example.
I would add:
In order to do this, I will first get people to put trees into the deserts. Once the deserts are fully planted with trees, I will ask construction workers to build homes. Families can move here and request to open shops if they wish.
Hope this helps!
Jacob Riis did not give away the explicit reason for the stench of the sink in the tenements. His only clue was the line "that all the tenants may have access", the reader would have to understand the living condition of the tenements for them to realize that the stench is the result of the over-populated tenement which lacked new plumbing.