Ice melts to form water. and water freezes to form ice. choose the true statement about these changes.
a. both melting and freezing are physical changes.
b. both melting and freezing are chemical changes.
c. melting is a physical change while freezing is a chemical change.
d. melting is a chemical change while freezing is a physical change.

An electromagnetic wave with frequency 65.0 hz travels in aninsulating magnetic material that has dielectric constant 3.64 andrelative permeability 5.18 at this frequency. the electric fieldhas amplitude 7.20 \times 10^{ - 3} {\rm v}/{\rm m}. a. what is the speed of propagation of the wave? b.what is the wavelength of the wave? c.what is the amplitude of the magnetic field? d.what is the intensity of the wave?