The symbol for a certain isotope of polonium is 
. How many neutrons are there in the nucleus of this isotope?
Definitions:
Banff
A town within the Banff National Park in Alberta, Canada, known for its mountainous surroundings and hot springs.
Restoration
The process of returning an ecosystem or habitat to its original state after it has been damaged or degraded.
Human Activities
Actions and behaviors carried out by humans that affect the natural environment, which can include agriculture, industry, and urban development.
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