If a star is located 100 light years from Earth, what can you conclude about the light from the star? The light will take 100 years to reach Earth.
The light will take 100 seconds to reach Earth.
The light will take 300,000 years to reach Earth.
The light will travel a total of 300,000 kilometers to reach Earth.

Light from star would take 100 years to reach the Earth.

Explanation:

1 light year = speed of light × 1 year

1 light year = 9.46 × 10¹⁵ m

hope i helped

-lvr

you'd use the equation that establishes a relationship between  energy  and  wavelength, which looks like this

e=h⋅cλ, where

λ  - the wavelength of the photon; c  - the speed of light, usually given as  3⋅108m/s; h  -  planck's constant, equal to  6.626⋅10−34j s

plug the value you were given for the energy of the photon in the above equation to get the wavelength

e=h⋅cλ⇒λ=h⋅ce

λ=6.626⋅10−34js⋅3⋅108ms−1.257⋅10−24j=1.581⋅10−1m