Question

fill in the blanks (a) the source of seismic waves can be found by an instrument which is known as___ (b) the passage of an electric current through an electrolyte causes___ effect. (c) air is a mixture of various gases , in which 78% is ___ gas. (d) the process of restoring areas of forests that once existed but have been deforested is called __

Answer 1

a seisminograph
c nitrogen
d afforeststation

Answer 2

hi don't know the answer