7. The measurement of the intensity of sound of two devices are given below. First device: Intensity of the sound from a vacuum cleaner = 70 dB (HA) Second device: Intensity of the sound from the machines at a construction site = 100 dB Which conclusion is correct on the basis of the given measurement? a. The wavelength of the second device is more than the wavelength of the first device. b. The frequency of the second device is more than the frequency of the first device. The amplitude of the second device is more than the amplitude of the first device. d. The velocity of the second sound device is more than the velocity of the first device C.​