People found directions at sea by the help of _______ before the compass was invented.
举一反三
- _______ magnetism first found a practical use. A: That was in the compass B: It was in the compass that C: It was the compass that D: That was the compass
- With the help of suspended magnetic element, a compass can aid people by ______ of the horizontal component of Earth's magnetic field.
- Before people found and utilized fossil-fuel in transportation, the energies to power vehicles are ( ).
- What was invented by Zhang Heng to detect a distant earthquake? A: star catalogue B: seismometer C: sundial D: compass
- There were not any other similar artistic forms like paper cutting before the paper was invented.