Use the equation to complete the activity. 21986 Rn + Beta→21985(1 point) Responses mass number is zero, it is a proton mass number is zero, it is a proton mass of beta is zero, and it is an electron mass of beta is zero, and it is an electron mass number is zero, and it is a neutron mass number is zero, and it is a neutron mass number is zero, it is a gamma. mass number is zero, it is a gamma.