The quantity, $Q$, of a drug in the blood stream begins with $300$ mg and decays to one-fifth its value over every $95$ minute period. Give the constants $a$, $b$, and $T$ so that $Q$ is represented by a function of the form $Q = ab^{-t/T}$, where $t$ is the time in minutes after the drug is injected.

$a =$ help (numbers)
$b =$ help (numbers)
$T =$ help (numbers)