Based on general principles of wave energy and the information you're asking to evaluate, here are the true statements regarding wave energy:
A. True. Letter J typically identifies the wavelength of a wave in diagrams.
C. True. Letter G is commonly used to represent the frequency of a wave in diagrams.
F. True. The wavelength of a microwave is indeed larger than that of an x-ray.
The other statements are false:
B. False. If letter J (wavelength) were longer, the wave would have less energy, not more. Energy is inversely related to wavelength in the context of electromagnetic waves.
D. False. If letter G (frequency) were longer, the wave would have less energy; energy is directly proportional to frequency.
E. False. Radio waves have the least energy among electromagnetic waves, while gamma rays or x-rays have the most energy.
So, the correct responses are A, C, and F.