About how much of the original 500 g of cobalt-60 will be left after 20 years?

it may be wrong but i think its a

answer: i don't know the answer good luck

explanation:

anchor = archer //

igneous rocks also form where plates converge. the subducting plate melts as it sinks into the crust of the earth, and the melt rises into the overriding plate forming volcanoes. metamorphic rocks are formed mainly in the lithosphere, wherever there is high pressure and high temperature. -woods