True or false: The Japanese learned about the Chinese inventions of gunpowder and printing.​

True

Explanation:

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

answer; i believe the correct answer is (a) the correlation between the cause variable and outcome variable is zero;