Two sets of parallel streets ( 48th & 49th streets and 16th and 17th avenue) intersect. if angle 15 is 50 degrees, how large is angle 6?
a) 40 degrees
b) 50 degrees
c) 130 degrees
d)140 degrees
e) insufficient information

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