I need to know which atom is left after the decay

Ababy stroller is a rest on top of a hill which is 10 m high. the stroller and baby have a mass of 20 kg. what is the potential energy of the baby and stroller?

An architect plans to use solar energy to heat the next house he designs. what principle of absorption and infrared energy can be applied to the design of the new house? how could she apply to those principals?

The protons in a nucleus are approximately 2 ✕ 10^−15 m apart. consider the case where the protons are a distance d = 1.93 ✕ 10^−15 m apart. calculate the magnitude of the electric force (in n) between two protons at this distance.