Scientists call them all electromagnetic radiation. The waves of energy are called electromagnetic (EM) because they have oscillating electric and magnetic fields. Scientists classify them by their frequency or wavelength, going from high to low frequency (short to long wavelength).
The work done by the elephant to lift one log is the force multiplied by the height at which the log has been lifted: And so, the total work done to lift the 7 logs is 7 times the work done to lift each log: