waves of frequency 20 hz are generated along spring. the distance between successive crests and troughs is 0.45m

Answer 1

What is your question?

Answer 2

you can determine the speed of the wave from the wave equation:

frequency*wavelength=speed
20hz*.90m=18m/s

Answer 3

V=DF
V=O.45×20hz
V= 9m/s