In a fixed-target experiment positrons are fired at a target of electrons at rest. What positron energy is required to produce a Z (mZ = 91.188 GeV)?

Am i correct on these two physics questions?

Based on its type of chemical bond, which of the following has the highest boiling point? potassium chloride ethyl alcohol water ammonia

By examining a wave’s pattern after it interacts with a barrier or gap, measurements can be made to better understand certain wave phenomena. what is a broad question you can answer by doing this experiment?