Which scenario involves the most work? a. pulling a box with a force of 127 newtons across the floor for 8 meters b. holding a mass with a force of 509 newtons in your arms for 150 seconds c. pushing against a brick wall with a force of 20 newtons for 42 seconds d. lifting a rock by exerting an upward force of 500 newtons for 1 meter

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.