Peter uses a old washing machine as anchor to park his boat. the machine weighs with water inside 405 kg, its size is 45 cm x 75 cm x 104 cm the static friction coefficient is 0.54. the lake is 95 m deep. a, how much horizontal force is needed to push the machine
b, how much vertical force is needed to push it up to the surface
c, what pressure does the machine have on the seafloor if it is laying on its longest side
d, what was the average speed if the machine fell to the floor in 1 minute and 26 seconds in m/s ​

d) physical means can be used to separate the components of air.

scattering of light by tiny particles in air to produce the colors we see on sky, is dependent on the following factors:

(i) wavelength of light

(ii) size of the scattering particle  

(iii) distance traveled by light through the atmosphere.

according to rayleigh's law of scattering, the amount of scattering is inversely proportional to the fourth power of its wavelength. shorter the wavelength, greater is its scattering. hence violet/blue light is scattered more than red.

sun's light is a composite light ( visible light) with wavelengths in the range 400 nm (violet) to 700 nm (red). as sunlight passes through our atmosphere, the molecules of air scatter light according to their wavelengths. during sunrise and sunset, the sun's position is below the horizon. hence light from the sun travels a greater distance in the atmosphere when compared to its position a noon.

as sunlight enters the earth's atmosphere, blue light is scattered away and at the end of its journey in the sky, only red and orange wavelengths remain in the beam.

hence at sunrise and sunset, the sky appears reddish orange.