What mass of fluorine-18 (F-18) is needed to have an activity of 1 mCi? How long will it take for the activity to decrease to 0.25 mCi?

probably not if net force is zero

first thing first of the answer is with technology. second thing second thing is that the big bang theory did not happened u see they say it did but what they dont realize is that like dinasures are still a round they might deny it but they and look at these 12 foot human skelteons they find lets see didnt the bible say something about giants. hope this peace.

answerdmitry mendeleyev made a workable classification of the elements