If you are laid $15 per $100 sold, what is your type of payment?

Commission

Explanation:

Not sure what you mean by "laid", but I believe you are describing commission.

answer: a. the kind of population living in your neighbourhood.

the census explorer data tool by the us census bureau allows the user to zoom in on any neighbourhood within the united states and find the kind of people residing in that by race and age.  

the tool needs to needs to be used twice – once in order to find what type of people reside in a neighbourhood, and then to see the age groups of the people in the same neighbourhood.

if it is for a job, then you should learn everything you can about the job, like what does it involve, what qualification is required and how you are the right person for that job. dress appropriately for the interview. get plenty of rest the night before. good luck!