What are three properties of electromagnetic waves? 1. They travel slower than the speed of light, they include visible light waves, and they can transfer energy through empty space.
2. They need matter through which to travel, they travel at the speed of light, and they include visible light waves.
3. They travel at the speed of light, they include ultraviolet waves, and they can transfer energy through empty space.
4. They include ultraviolet waves, they need matter through which to travel, and they travel slower than the speed of light.

beta is electron from nucleus

something from nucleus has changed, but charge must be same for cons of charge

the components of a vector are the parts of the vectors that are to each other.

b perpendicular

the answer is 100. i just did this lesson and got a 100% on it. : )

-fishtank

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