Abe, Belle, and Cathy have a total of $179.50. Abe has $9 more than Belle. Cathy has three times as much as Abe. How much money does Belle have?

Identify all the cases where non-probability sampling is used when attempting to study the characteristics of a large city. studies on every subject in the population divide a population in groups and obtain a sample studies with a limited amount of time demonstrate existing traits in a population studies with the nth person selected