Aguitar string has a length of 0.90 m. when you pluck it, it plays a “c” that has a frequency of 256 hz. how fast is the wave moving back and forth along the string?

plzzz explain how you got the

Which lists the fundamental forces in order, from strongest to weakest? strong nuclear, weak nuclear, electromagnetic, gravitational strong nuclear, electromagnetic, weak nuclear, gravitational gravitational, weak nuclear, electromagnetic, strong nuclear electromagnetic, gravitational, strong nuclear, weak nuclear