Answer:
the answer would be 500 milligrams
(sorry about the answer before- I accidentally went the wrong way, but i fixed the answer)
Hey there! :)
Answer:
y = 0, also known as the x-axis.
Step-by-step explanation:
The equation
is an exponential function.
There is an asymptote at y = 0, or the x-axis because:

An exponential function, unless containing a vertical shift, can never cross the x-axis resulting in an asymptote at y = 0.