What can be done to change the speed of waves on a string? check all that apply.

Awave has a wavelength of 7 mm and a frequency of 19 hertz. what is its speed?

What happens when the number of protons in an atom changes

The two most prominent wavelengths in the light emitted by a hydrogen discharge lamp are 656(red) and 486 (blue). light from a hydrogen lamp illuminates a diffraction grating with 500 lines per mm, and the light is observed on a screen 1.50 behind the grating. what is the distance between the first-order red and blue fringes?