Dr. Edward is testing the same individuals repeatedly over time as part of a research study, while Dr. Janice is comparing the performance of different people of various ages at the same time. Dr. Edward is using a research design; Dr. Janice is using a design.

Longitudinal and cross sectional

Explanation:

Dr. Edward is testing the same individuals repeatedly over time as part of a research study, while Dr. Janice is comparing the performance of different people of various ages at the same time. Dr. Edward is using a LONGITUDINAL research design; Dr. Janice is using a CROSS SECTIONAL design.

Dr. Edward is using a longitudinal research design.

Dr. Janice is using a cross-sectional research design.

Explanation:

A longitudinal study also known as longitudinal research design is a type of study in which repeated observations are made on a particular set of variables (e.g. same individuals) over a long or short period of time.

On the other hand, a cross-sectional study also known as cross-sectional research design is a type of study in which observations are made on different variables (e.g. different people) at the same time.

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.

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