[填空题]
What minimum amount of electroma ahrd6w p ds21:v-q+swzow6h8 gnetic energy is needed to 74 w4)tm xopl8sai* h26gtl 6tr u1ddyproduce an electron and a positron together? A positron is a particle with the same rest mass as an electron, but has the opposite charg*6mthxro4)2w6 1yu 87 alidpls tdg4te. (Note that electric charge is conserved in this process.) E = MeV
