It is noted that a sample of 134la with a half-life of 6.5 minutes has an activity of 2.6 ci. what was its activity 72 minutes ago?

This is what i found on google “according to the collision theory, the following criteria must be met in order for a chemical reaction to occur: molecules must collide with sufficient energy, known as the activation energy, so that chemical bonds can break. molecules must collide with the proper orientation.” i hope this information you.