Answer: The amount of carbon-14 left after 10 years is 25 g
Explanation:
Formula used :

where,
a = amount of reactant left after n-half lives = ?
= Initial amount of the reactant = 100 g
n = number of half lives =
Putting values in above equation, we get:


Therefore, the amount of carbon-14 left after 10 years is 25 g
Since transition metals with partially filled d orbitals have color when in solution. Therefore which ever solution has some color will likely contain a transition metal with a partially filled d orbital.
an example of this is solution with Cu²⁺ will have a blue tint to it.
A is the anwser. Fuel in the ocean would cause pollution