Consider y1 = t 2 and y2 = t|t|, namely, y2(t) = ( t^2 if t ≥ 0 −t ^ if t < 0 show that y1, y2 are linearly independent on (−∞, ∞) and yet w(y1, y2)(t) = 0 for all t.

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