How many publications are related to green nanoparticles?

If you mean nanoparticles for environmental applications then let's see…

2018, more than 166,000 articles related to nanotechnology were published, indicating an increase of more than 7% compared to the corresponding period last year.

No specific category for the environment is disclosed. However, I would say at least 3/4 are related to climate change or environmental

B is the correct answer. Railroads and the people who built them were able to form corporations that raised vast sums of money by giving stocks and bonds to their investors in exchange for those funds, which in turn, made them able to further expand the reaches of their companies.