Henrik is interested in how children in different cultures select their playmates in terms of matching gender, personality, age, and size. He does preliminary work observing school children at recess at a local elementary school near his home in Stockholm, Sweden. Henrik develops a method for coding the information he wants, and then uses the method to collect data at schools in Stockholm, Tokyo, Jakarta, and Nairobi. The approach he is using would be classified as:

first, the romans stayed isolated because they had to defend their own territories from neighboring cities that were harassing them, like the etruscans. second, once the romans managed to defeat their neighbors, and started to expand their territory, they started to build roads and bridges. finally, now that the romans have covered their territory with roads functioning as highways, they could mobilize their legions faster to assemble larger military units in a specific place.

good question. i'll be looking into that. (this is a joke sir)

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 .