How are the Feudal system and the Encomienda system similar? How are they different?

Is when a person has given their consent based on understanding the actions and facts of a study?

Pj conducts an experimental study on the effects of soft music during high stakes science testing. he randomly assigns students at the school. in one condition he does not provide music for testing while in the other group he does provide the music. he administers a pretest at the beginning of the year and a posttest at the end of the year. pj’s design is best described as a: a.static group comparisonb. pretest-posttest control group designc.control-group-time-series designd. nonrandomized control-group pretest-posttest design

Acurb of this color means you may not stop a) yellow b)green c) red d) blue