One of the main contaminants of a nuclear accident, such as that at chernobyl, is strontium-90, which decays exponentially at a rate of approximately 2.5% per year.

(a) write the ratio of strontium-90 remaining, p , as a function of years, t , since the nuclear accident.

Step-by-step explanation:

We know that the general form of the exponential decay formula is

, where y is final amount remaining after t time, A is the original amount and r is the rate of decay

Now, the ratio of strontium-90 remaining, p , as a function of years, t , since the nuclear accident.

Hence, the ratio of remaining since the nuclear accident is

the answer to your question is c.)   volcanoes built the mountains and earthquakes tore them down.

step-by-step explanation: