A researcher is examining cooperation between peers by observing children at six years, eight years, and ten years old. If the researcher uses a cross-sectional design and obtains 20 scores for each age, how many children participated in the entire study?

changes in factors like average income and preferences can cause an entire demand curve to shift right or left. this causes a higher or lower quantity to be demanded at a given price. demand curves relate the prices and quantities demanded assuming no other factors change. it is important for consumers to know this information, because it is crucial for them to know what they can afford and can't afford. i hope this .

answer; motor learning;

answer; omb;