The speed of light is 2.998 x 108 m/s. What wavelength of light has a frequency of 6.42 x 1019 Hz?

Which type of reaction always has an element and a compound as reactants

Diffraction is when light is bent around obstructions. which of the these observation about clouds would indicate diffraction? a) after rain storms, you can sometimes see rainbows. b) clouds are white or gray and cannot be seen through. c) on a cloudy day, the temperature tends to be cooler than a sunny day. d) the edges of dark clouds appear lighter. this

How do you lengthen a pattern piece? (family and consumer science, sewing)