If the frequency of the wave above was 4 Hz. what was the velocity of the wave?

Evaporation: this is when warmth from the sun causes water from oceans, lakes, streams, ice and soils to rise into the air and turn into water vapour (gas). water vapour droplets join together to make clouds! condensation: this is when water vapour in the air cools down and turns back into liquid water.

Answer) by studying proton collisions hope this : )

They are like other investigations? say there was a murder u have to do blood test and finger prints which run through a lab.