Answer:
Green, Blue, Indigo, Violet
Explanation:
According to Einstein's equation of photoelectric effect, the kinetic energy of emitted photoelectron is the difference between the energy of the incident photon and the work function of the metal. The work function of the metal referee to the minimum energy that must be supplied in order to eject an electron from a metal surface. The energy of the incident photon must exceed the work function of the metal.
When we look at the electromagnetic spectrum, only the selected colours have frequency above the threshold frequency as shown by the image attached below.
Answer: Eutrophication is the enhancement of the growth of algae in the water body.
Explanation:
The scientists are worried for the climate change as if the climate changed to prolonged rainy then the frequent raining can remove toxic chemicals from the agricultural sites, landfills, industries, and from other locations and deposit them to the water body (river, lakes, ponds, and others). The deposition of the salts of nitrogen, phosphorus, and sulfur promotes the growth of algae in the water body. This leads to reduction in the concentration of oxygen in the water body. This is called eutrophication. The lack of oxygen can lead to mortality of aquatic animals.