Red and green light have wavelengths of about 650 nm and 490 nm, respectively. which light has the highest frequency

1. Red, orange, yellow, green, violet. 
2. When elections return to their normal, or ground-state position, engery is emitted. When energy is absorbed, electrons within the atoms of substances are excited to higher positions of potential energy. 
3. Green light has a higher frequency and a higher energy. (Lower wavelengths mean higher energy and frequency both.) 
4. No, a spectroscope could not be used to detect that emission because 285 nm is not in the visible light color spectrum (400-about 700 nm). ((this one I am least sure about, someone else helped with this one)) 
5. Should be green light because that is 495-570nm. 
6. the slit in the spectroscope allows a narrow, collimated beam of light to be admitted. 

The answer is a 0.64 volts