The half life of substance A is $16$ years, and substance B decays at a rate of $30$ % each decade.

(a) Find a formula for a function $f(t)$ that gives the amount of substance A, in milligrams, left after $t$ years, given that the initial quantity was $100$ milligrams.
$f(t)=$ help (formulas)

(a) Find a formula for a function $g(t)$ that gives the amount of substance B, in milligrams, left after $t$ years, given that the initial quantity was $100$ milligrams.
$g(t)=$ help (formulas)

(c) Of which substance is there less in the long term?

A. There is less of substance B in the long term.
B. There is less of substance A in the long term.
C. There is no way to tell.