A visco-elastic material is one with both the properties of a liquid and the properties of an elastic solid. The combination of these two types of properties is excellent when it comes to absorbing or spreading energy because these two types of materials deal with energy in different ways.
Electric and magnetic fields (EMF) are invisible lines of force that surround any electrical device. Electrical wiring, electrical equipment and power lines all produce electric and magnetic fields. Electrical fields and magnetic fields can be characterized by their wavelength, frequency and amplitude (strength).
Choice 1 is correct. To detect the electric fields, use a conducting rod. The fields cause charges (generally electrons) to accelerate back and forth on the rod, creating a potential difference that oscillates at the frequency of the EM wave and with an amplitude proportional to the amplitude of the wave.