∠aob is shown on a coordinate plane. select all of the following transformations that would preserve the measure of ∠aob . answer choices reflection in the x -axis counterclockwise rotation by 90° the translation p(x, y)→p′(x+2,y+3) the horizontal dilation p(x, y)→p′(2x, y)

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