1) Alpha decay (radiation) emits a) 2 neutrons and 2 protons (helium nucleus) b) a high speed electron c) an electromagnetic wave 2) Beta decay (radiation) emits a) 2 neutrons and 2 protons (helium nucleus) b) a high speed electron c) an electromagnetic wave 3) Gamma decay (radiation) emits a) 2 neutrons and 2 protons (helium nucleus) b) a high speed electron c) an electromagnetic wave 4) Alpha particles are stopped by a) paper b) skin c) both of these 5) Beta particles are stopped by a) thin aluminium b) skin c) paper d) thick lead 6) Gamma particles are stopped by a) thin aluminium b) skin c) paper d) thick lead

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