I believe the answer is Observational study
In an observational study, the data input couldn't be controlled by researchers because it's relative to the subject.
This type of study usually being conducted in researchers that involve ethical measurement or Personal opinion.
Atahualpa was the ruler of Quito and subsequently ruled the Inca Empire before Spanish conquest. During the Spanish conquest, Atahualpa offered to fill a large room with gold and silver as a ransom to regain his freedom and to avoid being killed by the Spaniards. Despite paying this ransom, Atahualpa was then executed by the conqueres as he was deemed too much of a liability. Before being executed he converted to Catholocism and was strangled to death.
Strangers and Minors i think i Could be wrong
Thanks to the physical properties of matter such as size, shape, and density, mixtures can also be separated back into their different kinds of matter. One way mixtures can be separated is through filtration. Filtration is the passing of matter through a filter to separate larger particles.
