i believe the answer is a Brainiest plz
Answer:Sources of lead emissions vary from one area to another. At the national level, major sources of lead in the air are ore and metals processing and piston-engine aircraft operating on leaded aviation fuel. Other sources are waste incinerators, utilities, and lead-acid battery manufacturers. The highest air concentrations of lead are usually found near lead smelters.
Explanation:
Answer:
Np-237, Ar-40.
Explanation:
Alpha particle is positively charged particle having a mass of 4 unit. Hence,when alpha is removed from any isotope it produces a element having mass 4 units less than original isotope that was before emission. Americium 241 isotopes used in the smoke detector which emit an alpha particle to produce neptunium-237.
Potassium-40 emits positron which is having negative charge to lower one proton and increase one neutron number in the particle and in such way it will produce
not 
I think B would be the most reasonable answer, the steps all seem to make sense