its the second one
Just passed on edge 2020
The function is y = 40 * 2^(x/2)
The graph is in the image attached
The function that models this growth is an exponencial function, that can be described with the following equation:
y = a * b^(x/n)
Where a is the inicial value, b is the rate of growth, x is the time and n is the relation between the time and the rate (the rate occurs for every two hours, so n = 2).
Then, using a = 40, r = 2 and n = 2, we have:
y = 40 * 2^(x/2)
If we plot this function, we have the graph shown in the image attached,
It is an exponencial graph, where the value of y increases very fast in relation to the increase of x.
the graph where it's going up (right)
if you double 40 it will be 80. double 80 and you get 160 etc etc. this means the total bacteria only grows and the graph has to go all the way up