Can someone me with question 2 and question 3?

Which step in naming unsaturated hydrocarbons is used for alkenes but not alkynes

The image shows a process that releases nuclear energy which statement best identifies the process shown the process must be fusion because energy is released the process must be fusion because of have your nucleus formed a smaller nuclei the process must be fission because a large nucleus breaks into smaller nuclei the process must be fission because neutrons are formed

The blackbody curve for a star name zeta is shown below. what is the peak wavelength for this star ?