Why would let() be used in rspec?

Which of these statements about Ruby on Rails 5 are false?

Which URL's will not be created by method resources :posts in routes.rb?

Which folder do not exist in folder “app” in Rails 5? (check any that apply)

Which of these filters do not exist in Rails controller? (check any that apply)

Which of these files are located by default in 'config' directory? (check any that apply)

Most elegant way to include a javascript file needed for only one page?

belongs_to: Represents the inverse of a has_one (or has_many) association.

What is the difference between Symbol and String?

If you want the standard restful routes for your person controller, how do you add that?

Where will routes.rb file appear?