Answer:
They can join a gym or a class to help keep themselves motivated to exercise.
Explanation:
Answer:
Part a)

Part b)


Part c)


Explanation:
Part a)
frequency of light will not change with change in medium but it will depend on the source only
so here frequency of light will remain same in both water and glass and it will be same as that in air



Part b)
As we know that the refractive index of water is given as

so the wavelength in the water medium is given as



Similarly the refractive index of glass is given as

so the wavelength in the glass medium is given as



Part c)
Speed of the wave in water is given as



Speed of the wave in glass is given as



Electrical Energy to ThermalEnergy Conversions.
1. A toaster draws electric current (electrical energy) from a wall outlet and converts these moving electriccharges into heat (thermal energy) in the filaments that turn red hot to cook your toast.
Part 2:
the law of conservation of energy states that the total energy of an isolated system in a given frame of reference remains constant—it is said to be conserved over time. Energy can neither be created nor destroyed; rather, it transforms from one form to another.
Hope I could help
source: wiki & soft schools