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



F=ma=m(change in velocity/change in time)
Number 1
F=ma
F=55kg(1.1ms^-1/1.6s)=37.8N
Number 2
F=ma
F=0.440kg(10ms^-1/0.02s)=220N
Number 3
F=ma
F=1400kg(15ms^-1/0.73s)=2.88*10^3N or 28,767N
Any questions please feel free to ask.
Shockers acts as a shock absorber in the vehicle making the ride comfortable. When vehicle goes on rough road then it gets shocks from the road deformities the springs present in the shockers provide counter force and thus making the vehicle stable ride without shock.
[I copied this from the internet, but hope it helps!]
Again I think you did not give the right constants. So I would use the correct constants for mass of moon and distance from earth to moon.
<span>The formula for force of attraction between any two bodies in the universe
F = GMm / r^2. (Newton's Universal law of Gravitation).
G = Universal gravitational constant, G = 6.67 * 10 ^ -11 Nm^2 / kg^2.
M = Mass of Earth. = 5.97 x 10^24 kg.
m = mass of moon = 7.34 x 10^22 kg.
r = distance apart, between centers = in this case it is the distance from Earth to the Moon
= 3.8 x 10^8 m.
(Sorry I could not assume with the values you gave, they are wrong, and if we use them we would be insulting Physics).
So F = ((6.67 * 10 ^ -11)*(5.97 x 10^24)*(7.34 * 10^22)) / (3.8 x 10^8)^2.
Punch it all up in your calculator.
I used a Casio 991 calculator, it should be one of the best in the world.Really lovely calculator, that has helped me a lot in computations like this. I am thankful for the Calculator.
F = 2.0240 * 10^ 20 N.
So that's our answer.
Hurray!!</span>
Number of barrels are 3.0. Each barrel contains 42 gallons of oil. Thus, total volume of oil will be 42×3=126 gallons.
Converting gallons into m^{3}
1 gallon=0.00378 m^{3}
Thus, 126 gallons=0.4769 m^{3}
Thickness of oil film is 2.5\times 10^{2} nm, converting it into meters as follows:
1 nm=10^{-9} m
Thus,
2.5\times 10^{2} nm=1.5\times 10^{-7}m
Now, volume V of oil is related to area A and thickness T as follows:
V=A×T
rearranging,
A=\frac{V}{T}=\frac{0.4769 m^{3}}{2\times 10^{-7}m}=2.38\times 10^{6}m^{2}
Thus, square meters of oil will be 2.38\times 10^{6}m^{2}