Answer:
The most important methods are:
-Gravimeters .
-Seismograph .
-Electricity meters.
-Tiltmeter.
And the most important method to predict volcanic eruption is calculate the volume and flow of magma.
Step-by-step explanation:
-Gravimeters capture the gravitational field to detect fluid magma.
-Seismographs are used to calculate the intensity of earthquakes caused by moving magma.
-Magma generates electric currents, for that electricity meters, are used to control the magnetic and magma increase.
-The tiltmeter is a sensor that uses a laser beam to find out if the magma level has dropped or increased and the difference between new and old data is calculated.
Three researchers had the idea of creating a method where the volume and flow of magma are calculated and together with the instruments for calculating eruptions, magma explosions can be predicted in a specific period.