What changes are observed in the speed of the harmonics of an open-end air column as the harmonic number is increased

Ahydroelectric plant takes energy from water and turns it into electrical energy. what are the transformations of energy in the water molecules that are used in the process of generating electricity this way?

Achlorine atom has 17 protons and 18 neutrons. what is its mass number? what is its atomic number?

The gun from the crime scene shows tool marks where the serial numbers are ground off. there are also tool marks on the bullets left behind. what information can the tool marks on the bullets and gun provide about the crime? what type of evidence does this information provide, individual or class?