Which of the following provides evidence that has earth scientists determine the age of the earth more precisely?
a. helium dating
b. earth's distance from the sun
c. radioactive dating
d. tree rings

By definition, we have to:

Radioactive dating is a technique used by scientists to determine the absolute age of different rocks, different minerals and organic remains.

This method has been carried out since 1905.

This method was developed by Ernest Rutherford as a method by which to determine the age of the Earth.

The method consists in studying the sample time by means of the relationship between the number of children isotopes with respect to the number of parent isotopes.

the following provides evidence that you have helped earth scientists determine the age of the earth more precisely:

C. Radioactive dating

c) up is the direction the magnetic force is acting on the charge.

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.