It was invented during the Han Dynasty. The device made farmers’ job easier and highly improved the agricultural output in China.What do you think this was?What might it be used for?The Seed Drill Earthquake Detector According to court records of the later Han Dynasty, a seismograph was ...
It is a take-home earthquake detector.3.How much does it cost to make the Qube? It costs less than ＄100. 答案细节理解题。(1)根据Vivien He is a high school student from Southern California,USA.(Vivien He是一名来自美国南加州的高中生。)可知,Vivien是一名来自美国南加州...
When was the first GPS invented? When was the catapult invented? When was the boneshaker invented? When was the metal detector invented? When was the surfboard invented? When was the compass invented? When was the abacus invented? When was the curling iron invented?