I can't figure out how to start this at all, please help

Question

The mass of a radioactive substance follows a continuous exponential decay model. A sample of this radioactive substance has an initial mass of 2522 kg and decreases continuously at a relative rate of 7% per day. Find the mass of the sample after three days.

Do not round any intermediate computations, and round your answer to the nearest tenth.

Answer 1

Po= 2522 kg

7% per day = decay rate = .07

what is the mass after 3 days?

A=Poe^rt where e=an irrational constant =about 2.718281828...

A=2522e^.21

= about 3142.6 kg after 3 days, rounded off to one decimal place