The speed of sound at sea level is normally about 340 m/s. A stationary fire alarm has a frequency of 15,000 Hz. An observer running towards the fire alarm hears a frequency of 15,300 Hz. What is the velocity of the observer?

Ultraviolet radiation is dangerous because it has a high enough energy to damage skin cells. what is the best explanation of the relationship between wavelength and wave energy? a) wave energy is related only to frequency, not wavelength. b) longer wavelengths have lower frequencies but higher energy. c) the shorter the wavelength, the lower the frequency and the higher the energy. d) the shorter the wavelength, the higher the frequency and the higher the energy.

X-ray crystallography is used to see the structure of molecules. scientists have used the technique to find the structure of cholesterol an important biological molecules knowledge of a structure of cholesterol is because it may affect?

Answer fast for brainliest! < 3 what type of image is formed by a reflecting telescope? a reduced virtual image a reduced real image an enlarged real image an enlarged virtual image