Carbon-14 is an element which loses exactly half of its mass every 5730 years. The mass of a sample of carbon-
14 can be modeled by a function, M, which depends on its age, t (in years).
We measure that the initial mass of a sample of carbon-14 is 741 grams.
Write a function that models the mass of the carbon-14 sample remaining t years since the initial
measurement.